Semiconductor device

ABSTRACT

To provide a technique capable of reducing the chip size of a semiconductor chip and particularly, a technique capable of reducing the chip size of a semiconductor chip in the form of a rectangle that constitutes an LCD driver by devising a layout arrangement in a short-side direction. In a semiconductor chip that constitutes an LCD driver, input protection circuits are arranged in a lower layer of part of a plurality of input bump electrodes and on the other hand, in a lower layer of the other part of the input bump electrodes, the input protection circuits are not arranged but SRAMs (internal circuits) are arranged.

CROSS-REFERENCE TO RELATED APPLICATION

This is a Continuation of U.S. patent application Ser. No. 15/587,718,filed May 5, 2017, abandoned, which is a Continuation of U.S. patentapplication Ser. No. 15/200,246, filed Jul. 1, 2016, now U.S. Pat. No.9,659,926, which is a Continuation of U.S. patent application Ser. No.14/712,689 filed May 14, 2015, now U.S. Pat. No. 9,391,066, which is aContinuation of U.S. patent application Ser. No. 14/028,755, filed Sep.17, 2013, abandoned, which is a Divisional of U.S. patent applicationSer. No. 12/793,431, filed Jun. 3, 2010, now U.S. Pat. No. 8,564,127,which claims priority to Japanese Patent Application No. 2009-173356filed on Jul. 24, 2009. The contents of the aforementioned applicationsare incorporated by reference in their entirety.

BACKGROUND OF THE INVENTION

The present invention relates to a semiconductor device, in particular,to the technology which is effective when applied to a semiconductordevice that is used as a driver for LCD (Liquid Crystal Display).

Japanese Patent Laid-Open No. 2006-210607 describes the techniquecapable of reducing the chip size. Specifically, buffers are arrangedcollectively in regions distant from pads, respectively. The regions arethe main region except for the regions where the central processingunit, the nonvolatile memory, and the volatile memory are formed. Thebuffers that require a large area are not provided in the pad peripheralpart, and therefore, it is possible to reduce the interval between thepads and the distance between the pad and the internal circuit (forexample, the central processing unit). Due to this, the chip size can bereduced.

Japanese Patent Laid-Open No. 2007-103848 describes the techniquecapable of reducing the size of a semiconductor chip. Specifically,first the pad and the wiring other than the pad are provided over theinsulating film. Over the insulating film including over the pad and thewiring, the surface protection film is formed and the opening isprovided in the surface protection film. The opening is formed over thepad and the surface of the pad is exposed. Over the surface protectionfilm including the opening, the bump electrode is formed. Here, the padis configured to have the size sufficiently smaller than that of thebump electrode. Due to this, the wiring is disposed immediately underthe bump electrode and in the same layer as that of the pad. That is,the wiring is disposed in the space under the bump electrode formed byreducing the size of the pad.

SUMMARY OF THE INVENTION

In recent years, an LCD that uses liquid crystal as a display elementhas been spreading rapidly. The LCD is controlled by a driver thatdrives the LCD. The LCD driver includes a semiconductor chip, and ismounted on a glass substrate. The semiconductor chip that constitutesthe LCD driver has a structure in which a plurality of transistors andmultilayer wirings are formed over a semiconductor substrate and bumpelectrodes are formed on the surface thereof. Then, the semiconductorchip is mounted on the glass substrate via the bump electrode formed onthe surface.

The semiconductor chip that constitutes an LCD driver is in the form ofa rectangle having short sides and long sides and a plurality of bumpelectrodes is arranged along the long-side direction of thesemiconductor chip. For example, along a first long side of a pair oflong sides, input bump electrodes are arranged linearly and along asecond long side in opposition to the first long side, output bumpelectrodes are arranged in a staggered manner. That is, thesemiconductor chip constituting an LCD driver is characterized in thatthe number of output bump electrodes is greater than that of input bumpelectrodes. This is because the input bump electrode receives mainlyserial data while the output bump electrode outputs parallel dataconverted by the LCD driver.

Accompanying the miniaturization of semiconductor elements, thedownsizing of the semiconductor chip constituting an LCD driver is alsobeing progressed. However, in the semiconductor chip constituting an LCDdriver, the length in the long-side direction is affected largely by thenumber of bump electrodes. That is, in a liquid crystal display device,the number of output bump electrodes of an LCD driver is substantiallydetermined, and therefore, the number of output bump electrodes cannotbe reduced and it is becoming difficult to reduce the long side of thesemiconductor chip constituting the LCD driver. That is, it is necessaryto form a predetermined number of output bump electrodes along the longside of the semiconductor chip constituting the LCD driver, however, thedistance between the bump electrodes has been reduced to a minimum, andtherefore, it is difficult to further reduce the length in the long-sidedirection of the semiconductor chip.

An object of the present invention is to reduce the chip size of asemiconductor chip.

The above-mentioned and the other purposes and the new feature of thepresent invention will become clear from the description of the presentspecification and the accompanying drawings.

The following explains briefly the outline of a typical invention amongthe inventions disclosed in the present application.

A semiconductor device according to a typical embodiment comprises asemiconductor chip in the form of a rectangle having a pair of shortsides and a pair of long sides. Here, the semiconductor chip includes(a) a plurality of first bump electrodes arranged along a first longside of the semiconductor chip and arranged at a position closer to thefirst long side than to a second long side in opposition to the firstlong side, (b) an internal circuit formed in the semiconductor chip, and(c) a plurality of first electrostatic protection circuits which protectthe internal circuit against static electricity and are electricallycoupled to the first bump electrodes. At this time, part of the firstelectrostatic protection circuits electrically coupled to part of thefirst bump electrodes are arranged at a position that overlaps the partof the first bump electrodes in a planar view, and the other firstelectrostatic protection circuits of the first electrostatic protectioncircuits electrically coupled to the other first bump electrodes of thefirst bump electrodes are arranged at a position different from aposition that overlaps the other first bump electrodes in a planar view.

A semiconductor device according to a typical embodiment comprises asemiconductor chip in the form of a rectangle having a pair of shortsides and a pair of long sides. Here, the semiconductor chip includes(a) a plurality of first bump electrodes arranged along a first longside of the semiconductor chip and arranged at a position closer to thefirst long side than to a second long side in opposition to the firstlong side, (b) an internal circuit formed in the semiconductor chip, and(c) a plurality of first electrostatic protection circuits which protectthe internal circuit against static electricity and are electricallycoupled to the first bump electrodes. At this time, the firstelectrostatic protection circuits are arranged at a position differentfrom a position that overlaps the first bump electrodes in a planarview.

A semiconductor device according to a typical embodiment comprises asemiconductor chip in the form of a rectangle having a first short side,a second short side in opposition to the first short side, a first longside, and a second long side in opposition to the first long side. Here,the semiconductor chip includes (a) first bump electrodes and secondbump electrodes arranged along the first long side of the semiconductorchip and arranged at a position closer to the first long side than tothe second long side and (b) an uppermost layer wiring arranged via aninsulating film at a position that overlaps the first bump electrode andthe second bump electrode in a planar view. Further, the semiconductorchip includes (c) a first opening formed in the insulating film in orderto be coupled to the first bump electrode and (d) a second openingformed in the insulating film in order to be coupled to the second bumpelectrode. At this time, the position where the first opening is formedrelative to the first bump electrode is different from the positionwhere the second opening is formed relative to the second bump electrodein the direction along the first short side or the second short side.

A semiconductor device according to a typical embodiment comprises asemiconductor chip in the form of a rectangle having a pair of shortsides and a pair of long sides. Here, the semiconductor chip includes(a) first bump electrodes and second bump electrodes arranged along afirst long side of the semiconductor chip and arranged at a positioncloser to the first long side than to a second long side in oppositionto the first long side and (b) an uppermost layer wiring arranged via aninsulating film at a position that overlaps the first bump electrode andthe second bump electrode in a planar view. The semiconductor chipfurther has (c) a first opening formed in the insulating film in orderto be coupled to the first bump electrode and (d) a second openingformed in the insulating film in order to be coupled to the first bumpelectrode. At this time, the uppermost layer wiring includes a firstuppermost layer wiring that is coupled to the first bump electrode viathe first opening and a second uppermost layer wiring which is coupledto the first bump electrode via the second opening and is different fromthe first uppermost layer wiring, and the first opening and the secondopening are formed so as to be coupled to the first bump electrode atdifferent positions.

A semiconductor device according to a typical embodiment comprises asemiconductor chip in the form of a rectangle having a first short side,a second short side in opposition to the first short side, a first longside, and a second long side in opposition to the first long side. Here,the semiconductor chip includes (a) first bump electrodes arranged alongthe first long side of the semiconductor chip and arranged at a positioncloser to the first long side than to the second long side in oppositionto the first long side, (b) an internal circuit formed in thesemiconductor chip, and (c) a first electrostatic protection circuitwhich protects the internal circuit against static electricity and iselectrically coupled to the first bump electrode. At this time, theinternal circuit is disposed at a position that overlaps the first bumpelectrode in a planar view and the first electrostatic protectioncircuit is arranged at a position different from a position thatoverlaps the first bump electrode in a planar view.

A semiconductor device according to a typical embodiment comprises asemiconductor chip in the form of a rectangle having a first short side,a second short side in opposition to the first short side, a first longside, and a second long side in opposition to the first long side. Here,the semiconductor chip includes (a) first bump electrodes arranged alongthe first long side of the semiconductor chip and arranged at a positioncloser to the first long side than to the second long side in oppositionto the first long side, (b) an internal circuit formed in thesemiconductor chip, and (c) a first electrostatic protection circuitwhich protects the internal circuit against static electricity and iselectrically coupled to the first bump electrode. At this time, thefirst electrostatic protection circuit is disposed at a positiondifferent from a position that overlaps the first bump electrode in aplanar view and a plurality of wirings passes at the position thatoverlaps the first bump electrode in a planar view.

The following explains briefly the effect acquired by the typicalinvention among the inventions disclosed in the present application.

It is possible to reduce the chip size of a semiconductor chip.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram showing a configuration of a semiconductor chipconstituting a general LCD driver;

FIG. 2 is a circuit block diagram showing an example of an inputprotection circuit;

FIG. 3 is a circuit block diagram showing another example of an inputprotection circuit;

FIG. 4 is a diagram showing a configuration of a semiconductor chipconstituting an LCD driver in a first embodiment of the presentinvention;

FIG. 5 is an enlarged view of a region in the vicinity of a long side ofa semiconductor chip constituting a general LCD driver;

FIG. 6 is an enlarged view of a region in the vicinity of a long side onthe side of an input bump electrode of a semiconductor chip, which is anLCD driver, in the first embodiment;

FIG. 7 is a diagram showing a configuration of a semiconductor chipconstituting an LCD driver in a second embodiment;

FIG. 8 is a diagram illustrating a first device point in a thirdembodiment;

FIG. 9 is a diagram illustrating a second device point in the thirdembodiment;

FIG. 10 is a diagram illustrating a third device point in the thirdembodiment;

FIG. 11 is a diagram showing an example of wiring layout that hasemployed the first to third device points in the third embodiment;

FIG. 12 is an enlarged view showing a semiconductor chip constituting anLCD driver in a fourth embodiment;

FIG. 13 is a diagram showing one input bump electrode in a fifthembodiment;

FIG. 14 is a section view cut along A-A line in FIG. 13;

FIG. 15 is a diagram showing one input bump electrode in the fifthembodiment;

FIG. 16 is a section view cut along A-A line in FIG. 15;

FIG. 17 is a section vies showing a manufacturing process of asemiconductor device in a sixth embodiment;

FIG. 18 is a section view showing the manufacturing process of asemiconductor device, following FIG. 17;

FIG. 19 is a section view showing the manufacturing process of asemiconductor device, following FIG. 18;

FIG. 20 is a section view showing the manufacturing process of asemiconductor device, following FIG. 19;

FIG. 21 is a diagram showing an overall configuration of an LCD (LiquidCrystal Device);

FIG. 22 is an enlarged view of a region in the vicinity of a long sideon the side of an output bump electrode of a semiconductor chip, whichis an LCD driver, in a seventh embodiment; and

FIG. 23 is a section view in an eighth embodiment, a section view cutalong A-A line in FIG. 13.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The following embodiments will be explained, divided into pluralsections or embodiments, if necessary for convenience. Except for thecase where it shows clearly in particular, they are not mutuallyunrelated and one has relationships such as a modification, details, andsupplementary explanation of some or entire of another.

In the following embodiments, when referring to the number of elements,etc. (including the number, a numeric value, an amount, a range, etc.),they may be not restricted to the specific number but may be greater orsmaller than the specific number, except for the case where they areclearly specified in particular and where they are clearly restricted toa specific number theoretically.

Furthermore, in the following embodiments, it is needless to say that anelement (including an element step etc.) is not necessarilyindispensable, except for the case where it is clearly specified inparticular and where it is considered to be clearly indispensable from atheoretical point of view, etc.

Similarly, it is assumed that, in the following embodiments, when theshapes, positional relationships, etc., of the components etc. arereferred to, except when explicitly stated in particular or when theycan apparently be thought otherwise in principle, those substantiallysimilar to or resembling the shapes etc. are also included. This alsoapplies to the above-mentioned numerical values and ranges.

In all of the drawings for explaining embodiments, the same symbol isattached to the same member, as a principle, and the repeatedexplanation thereof is omitted. In order to make a drawing intelligible,hatching may be attached even if it is a plane view.

First Embodiment

For an LCD driver, the downsizing of a semiconductor chip is progressedas described above, and in particular, the reduction of a semiconductorchip in the short-side direction has been examined.

First, an external configuration of a general LCD driver will bedescribed. FIG. 1 is a plan view showing the surface of a semiconductorchip CHP1 constituting an LCD driver. In FIG. 1, the semiconductor chipCHP1 has a semiconductor substrate formed into the form of, for example,an elongated rectangle (form of a rectangle), and over the main surfacethereof, an LCD driver that drives a display device, such as a liquidcrystal display device, is formed.

The semiconductor chip CHP1 is in the form of a rectangle having a pairof short sides (short side SS1 and short side SS2) and a pair of longsides (long side LS1 and long side LS2) and along one of the pair oflong sides, that is, the long side LS1 (side on the lower side in FIG.1), a plurality of input bump electrodes IBMP is arranged. These inputbump electrodes IBMP are arranged linearly. The input bump electrodeIBMP functions as an external connection terminal to be coupled to anintegrated circuit (LSI (Large Scale Integration)) includingsemiconductor elements and wirings formed inside the semiconductor chipCHP1. In particular, the input bump electrode IBMP is a bump electrodefor a digital input signal or analog input signal.

Next, along the other of the pair of long sides, that is, the long sideLS2 (side on the upper side in FIG. 1), a plurality of output bumpelectrodes OBMP is arranged. These output bump electrodes OBMP arearranged in two rows along the long side LS2 and the output bumpelectrodes OBMP in the two rows along the long side LS2 are arranged ina staggered manner. Due to this, it is possible to arrange the outputbump electrodes OBMP highly densely. The output bump electrode OBMP alsofunctions as an external connection terminal to couple the integratedcircuit formed inside the semiconductor substrate to outside. Inparticular, the output bump electrode OBMP is a bump electrode for anoutput signal from the integrated circuit.

As described above, along the pair of the long side LS1 and the longside LS2 constituting the outer circumference of the semiconductor chipCHP1, the input bump electrodes IBMP and the output bump electrodes OBMPare formed as a result. At this time, the number of the output bumpelectrodes OBMP is greater compared to the number of the input bumpelectrodes IBMP, and therefore, while the input bump electrodes IBMP areformed linearly along the long side LS1, the output bump electrodes OBMPare arranged along the long side LS2 in a staggered manner. This isbecause while the input bump electrode IBMP is a bump electrode for aninput signal to be input to an LDC driver, the output bump electrodeOBMP is a bump electrode for an output signal to be output from an LCDdriver. That is, an input signal to be input to an LCD driver is serialdata, and therefore, the number of the input bump electrodes IBMP, anexternal connection terminal, is not so great. In contrast to this, anoutput signal to be output from an LCD driver is parallel data, andtherefore, the number of the output bump electrodes OBMP, an externalconnection terminal, is great. That is, the output bump electrode OBMPis provided corresponding to each individual cell (pixel) constituting aliquid crystal display element, and therefore, the number of the outputbump electrodes OBMP needs to be that corresponding to the number ofrows and columns (for example, gate line, source line) for drivingcells. Because of this, the number of the output bump electrodes OBMP isgreater than that of the input bump electrodes IBMP. As a result of theabove, it is possible to arrange the input bump electrodes IBMP alongthe long side LS1 linearly, however, the output bump electrodes OBMP arearranged along the long side LS2 in a staggered manner so that thenumber of the output bump electrodes OBMP that can be arranged isincreased.

In FIG. 1, the input bump electrodes IBMP and the output bump electrodesOBMP are arranged, respectively, along the pair of the long side LS1 andthe long side LS2 constituting the semiconductor chip CHP1, however, itis also possible to further arrange them along the pair of the shortside SS1 and the short side SS2, in addition to the pair of the longside LS1 and the long side LS2.

The external configuration of the semiconductor chip CHP1 is asdescribed above, and the function of an LCD driver that is realized byan integrated circuit formed in the semiconductor chip CHP1 will bedescribed below. FIG. 1 also shows a functional block showing thefunction of an LCD driver. In FIG. 1, the semiconductor chip CHP1 has acontrol part 1, an SRAM (Static Random Access Memory) 2 a and an SRAM 2b, which are a memory circuit, an input protection circuit(electrostatic protection circuit) 3, and an output protection circuit(electrostatic protection circuit) 4. The control part 1 is configuredso as to include, for example, an LCD control part and an analog part,and the SRAM 2 a and SRAM 2 b include, for example, a memory cell arrayin which memory cells (storage element) of SRAM are arranged in amatrix, an SRAM control part that drives the memory cell array, and aword driver. Further, the input protection circuit 3 and the outputprotection circuit 4 are configured, for example, as a part of an inputcircuit, an output circuit, or an I/O circuit, which is an input/outputcircuit.

The I/O circuit has a function to input/output data to be input to andoutput from the semiconductor chip CHP1, and the SRAMs 2 a, 2 b are anexample of a storage circuit (memory circuit) that stores data. TheSRAMs 2 a, 2 b have a structure in which storage elements that storedata are arranged in an array and store data of images etc. to bedisplayed in a liquid crystal display device. The word driver has afunction to select a row of the SRAMs 2 a, 2 b arranged in an array(matrix) and the SRAM control part has a function to control the writingof data to and reading data from the SRAMs 2 a, 2 b. That is, the SRAMcontrol part includes an address decoder and a read/write controlcircuit to control the reading and writing of the SRAMs 2 a, 2 b.

The LCD control part has a function to generate access signals for amicrocomputer to be mounted outside the LCD driver (semiconductor chipCHP1), timing signals to operate the SRAMs 2 a, 2 b and an internalcircuit required to produce a display of a counter, etc., and comprisesa reset circuit to reset a display, a clock circuit to generate a clocksignal, etc. Further, the analog part has a function (level shiftfunction) to, for example, increase the voltage level of image datastored in the SRAMs 2 a, 2 b and convert the voltage into a voltagesuitable to a liquid crystal display cell etc. That is, the analogcircuit is configured so as to include a step-up circuit to increase avoltage and so as to generate various voltages to be applied to a liquidcrystal display cell.

The input protection circuit 3 is a circuit having a function to protectinternal circuits (SRAM, word driver, SRAM control part, LCD controlpart, analog part, etc.) against a surge voltage applied accidentally tothe input bump electrode IBMP. Here, a surge voltage refers to anabnormal voltage induced instantaneously by static electricity etc.Similarly, the output protection circuit 4 is a circuit that protectsthe internal circuit against a surge voltage applied accidentally to theoutput bump electrode OBMP. By providing the input protection circuit 3and the output protection circuit 4 as described above, it is possibleto protect the internal circuit that realizes the function of the LCDdriver against static electricity etc.

A configuration example of the input protection circuit 3 and the outputprotection circuit 4 will be described below. FIG. 2 is a diagramshowing a configuration example of the input protection circuit 3provided between the input bump electrode IBMP and an internal circuitIU. In FIG. 2, the input protection circuit 3 is coupled between theinput bump electrode IBMP and the internal circuit IU. That is, theinput bump electrode IBMP and the internal circuit IU are electricallycoupled via the input protection circuit 3. The internal circuit IUrefers to, for example, a circuit that includes the control part 1, theSRAMs 2 a, 2 b, etc. As shown in FIG. 2, the input protection circuit 3has a diode D1 and a diode D2. The anode of the diode D1 is coupled to aground potential Vss and the cathode of the diode D1 is coupled to apoint A to couple the input bump electrode IBMP and the internal circuitIU. On the other hand, the anode of the diode D2 is coupled to the pointA and the cathode of the diode D2 is coupled to a power source potentialVdd. The input protection circuit 3 is configured as described above andits operation will be described below.

First, the normal operation will be described. When an input voltage isapplied to the input bump electrode IBMP, the potential at the terminalA becomes a predetermined potential. At this time, the potential at theterminal A is higher than the ground potential Vss and lower than thepower source potential Vdd. Because of this, when the diode D1 isconsidered, the cathode of the diode D1 (potential at the terminal A) ishigher in potential than the anode of the diode D1 (ground potentialVss), and therefore, no current flows through the diode D1. Similarly,when the diode D2 is considered, the cathode of the diode D2 (powersource potential Vdd) is higher in potential than the anode of the diodeD2 (potential at the terminal A), and therefore, no current flowsthrough the diode D2. As described above, in the normal operation, nocurrent flows through the diode D1 or the diode D2, and therefore, aninput voltage (input signal) input to the input bump electrode IBMP isoutput to the internal circuit IU.

Subsequently, an abnormal operation will be described. For example, acase is considered, where a surge voltage is applied to the input bumpelectrode IBMP due to the influence of static electricity etc.Specifically, when a positive voltage greater than the power sourcepotential Vdd is applied as a surge voltage, a positive voltage greaterthan the power source potential Vdd is applied to the terminal A towhich the cathode of the diode D1 is coupled. Because of this, to thediode D1, a great backward voltage is applied, causing breakdown, and abackward current flows from the terminal A toward the ground potentialVss. On the other hand, a positive voltage greater than the power sourcepotential Vdd is applied to the anode of the diode D2, and therefore, aforward current flows through the diode D2 from the terminal A towardthe power source potential Vdd. As described above, when a positivevoltage greater than the power source potential Vdd is applied as asurge voltage, the diode D1 breaks down in the backward direction andthe diode D2 turns on in the forward direction, and therefore, it ispossible to let charges accompanying the surge voltage escape to thepower source line or the ground line. As a result of that, it ispossible to prevent the internal circuit IU from being destroyed by theapplication of a high voltage.

Similarly, when a negative voltage of absolute value greater than theground potential Vss is applied as a surge voltage, a negative potentialsmaller than the ground potential Vss is applied to the terminal A towhich the cathode of the diode D1 is coupled. Because of this, a forwardvoltage is applied to the diode D1 and a forward current flows from theground potential Vss toward the terminal A. On the other hand, a greatnegative potential is applied to the anode of the diode D2, andtherefore, a great backward voltage is applied to the diode D2, thediode D2 breaks down, and a backward current flows from the power sourcepotential Vdd toward the terminal A. As described above, when a greatnegative voltage is applied as a surge voltage, the diode D2 breaks downin the backward direction and the diode D1 turns on in the forwarddirection, and therefore it is possible to let charges accompanying thesurge voltage escape to the power source line and the ground line. As aresult of that, it is possible to prevent the internal circuit IU frombeing destroyed by the application of a high voltage.

Further, FIG. 3 is a diagram showing another configuration example ofthe input protection circuit 3 provided between the input bump electrodeIBMP and the internal circuit IU. In FIG. 3, the input protectioncircuit 3 is coupled between the input bump electrode IBMP and theinternal circuit IU. That is, the input bump electrode IBMP and theinternal circuit IU are electrically coupled via the input protectioncircuit 3 as a result. The internal circuit IU refers to, for example, acircuit that includes the control part 1, the SRAMs 2 a, 2 b, etc. Asshown in FIG. 3, the input protection circuit 3 has an n-channel typeMISFET Tr1 and a p-channel type MISFET Tr2. In the n-channel type MISFETTr1, a drain region is coupled to the terminal A and a source region anda gate electrode are coupled to the ground potential Vss. On the otherhand, in the p-channel type MISFET Tr2, the drain region is coupled tothe terminal A and the source region and the gate electrode are coupledto the power source potential Vdd.

In the input protection circuit 3 also, which has the above-describedconfiguration, when a surge voltage is applied to the terminal A fromoutside, one of the n-channel type MISFET Tr1 and the p-channel typeMISFET Tr2 turns on in accordance with the polarity of the surge voltageand the other breaks down between the source region and the drainregion. Due to this, it is possible to let charges accompanying thesurge voltage escape to the power source line and the ground line. As aresult of that, it is possible to prevent the internal circuit IU frombeing destroyed by the application of a high voltage. As describedabove, the configuration example of the input protection circuit 3 isdescribed, and the output protection circuit 4 has a configurationsimilar to that of the input protection circuit 3.

The main functions of the LCD driver are realized in the functionalblocks described above, and these functional blocks are arranged so asto stand side by side in the long-side direction of the semiconductorchip CHP1 in the form of a rectangle as shown in FIG. 1, for example.Each functional block constituting the LCD driver includes MISFET formedover the semiconductor substrate and multilayer wirings formed over theMISFET, respectively. At this time, for example, the SRAM control partand the LCD control part are formed by a digital circuit and the analogpart is formed by an analog circuit. The SRAM control part and the LCDcontrol part are formed by a digital circuit, however, the MISFETconstituting the digital circuit includes a low withstand voltage MISFEThaving an operating voltage of small absolute value. That is, the SRAMcontrol part and the LCD control part include a logic circuit andthereby the degree of integration is increased. Because of this, thefiner the MISFET becomes, the lower the absolute value of the operatingvoltage of the MISFET becomes. Because of this, the SRAM control partand the LCD control part use a low withstand voltage MISFET having anoperating voltage of the smallest absolute value among the LCD drivers.For example, the absolute value of the operating voltage of the lowwithstand voltage MISFET used in the LCD control part is about 1.5 V.

On the other hand, the analog part includes an analog circuit and theMISFET constituting the analog circuit includes a high withstand voltageMISFET having an operating voltage of the absolute value comparativelyhigher than that of the low withstand voltage MISFET. This is becausethe analog circuit has a function to convert the voltage level of imagedata and apply a voltage of a medium or high voltage (a few tens of V)to the liquid crystal display cell. As described above, in thesemiconductor chip CHP1 constituting the LCD driver, a plurality ofkinds of MISFET having an operating voltage of different absolute valuesis formed and in particular, in the SRAM control part and the LCDcontrol part, a low withstand voltage MISFET having an operating voltageof the smallest absolute value is used. In contrast to this, in theanalog part, a high withstand voltage MISFET having an operating voltageof the comparatively high absolute value is used. Further, as the MISFETused in the input protection circuit 3 or the output protection circuit4 described above, a high withstand voltage MISFET is used. The absolutevalue of operating voltage of these high withstand voltage MISFETs is,for example, about 20 to 30 V.

Next, the operation of the LCD driver will be described briefly. First,serial data to display an image is input from a microcomputer etc.mounted outside the LCD driver (semiconductor chip CHP1). The serialdata is input to the LCD control part via an I/O circuit. The LCDcontrol part having received the serial data converts the serial datainto parallel data based on a clock signal generated in a clock circuit.Then, the LCD control part outputs a control signal to the SRAM controlpart to store the converted parallel data in the SRAMs 2 a, 2 b. TheSRAM control part, when receiving the control signal from the LCDcontrol part, activates the word driver and causes the SRAMs 2 a, 2 b tostore image data, which is parallel data. Then, the SRAM control partreads the image data stored in the SRAMs 2 a, 2 b at a predeterminedtiming and outputs it to the analog part. The analog part converts thevoltage level of the image data (parallel data) and outputs the imagedata from the LCD driver. The image data (parallel data) output from theLCD driver is applied to each individual liquid crystal display cell andthus an image is displayed. Thus, it is possible for the LCD driver todisplay an image in the liquid crystal display device.

In the semiconductor chip CHP1 constituting a general LCD driver shownin FIG. 1, the input bump electrodes IBMP are formed along the long sideLS1 and the output bump electrodes OBMP are formed along the long sideLS2. Here, the output bump electrodes OBMP are provided so that thenumber of the output bump electrodes OBMP arranged along the long sideLS2 corresponds to the number of row and column lines (for example, gateline, source line) that drive cells, and the number is greater than thenumber of the input bump electrodes IBMP arranged along the long sideLS1. Because of this, the length in the long-side direction of thesemiconductor chip CHP1 constituting the LCD driver is substantiallyregulated by the number of the output bump electrode OBMP, which isgreater than that of the input bump electrodes IBMP. Because of this,when the number of the output bump electrodes OBMP is regulated, itbecomes difficult to reduce the length in the long-side direction of thesemiconductor chip CHP1 constituting the LCD driver. Further, when thearrangement of the output bump electrodes OBMP arranged in the long-sidedirection of the LCD driver is changed to another, it is required tochange the layout of the wirings that couple the display part of theliquid crystal display device that mounts the LCD driver and the LCDdriver. Normally, the LCD driver is delivered to a maker thatmanufactures the display part of the liquid crystal display device andthen the LCD driver is mounted in the liquid crystal display device. Atthis time, the maker that manufactures the liquid crystal display devicedoes not desire to change the configuration of the display part, andtherefore, the arrangement of the output bump electrodes OBMP to bearranged in the long-side direction of the LCD driver is regulated inadvance. Because of this, it becomes difficult to change the arrangementand the number of the output bump electrodes OBMP to be formed in theLCD driver. This also forms a factor to make it difficult to reduce thelong side of the semiconductor chip CHP1 constituting the LCD driver.Despite the above, accompanying the miniaturization of a semiconductorelement, the reduction in chip size of the semiconductor chip CHP1constituting the LCD driver has been desired. Because of this, it hasbeen examined to reduce the size in the short-side direction of thesemiconductor chip CHP1 in an attempt to reduce in size thesemiconductor chip CHP1 constituting the LCD driver. Hereinafter, atechnical idea will be described which can reduce the length in theshort-side direction of the semiconductor chip CHP1 constituting the LCDdriver by devising the layout configuration of the semiconductor chipCHP1.

FIG. 4 is a diagram showing a layout configuration of a semiconductorchip CHP2 in the present first embodiment. In FIG. 4, the semiconductorchip CHP2 in the present first embodiment is in the form of a rectanglehaving a pair of the short side SS1 and the short side SS2 and a pair ofthe long side LS1 and the long side LS2 as in the general semiconductorchip CHP1 shown in FIG. 1. Then, the input bump electrodes IBMP arearranged along the long side LS1 at a position closer to the long sideLS1 than to the long side LS2 in opposition to the long side LS1. On theother hand, the output bump electrodes OBMP are arranged along the longside LS2 at a position closer to the long side LS2 than to the long sideLS1 in opposition to the long side LS2. Further, the semiconductor chipCHP2 in the present first embodiment has the control part 1, the SRAMs 2a, 2 b, and an SRAM 2 c, input protection circuits 3 a to 3 c, and theoutput protection circuit 4 as in the general semiconductor chip CHP1shown in FIG. 1. The input protection circuits 3 a to 3 c are configuredso as to protect the internal circuit from static electricity and to beelectrically coupled to the input bump electrodes IBMP, and the outputprotection circuit 4 is also configured so as to protect the internalcircuit from static electricity and to be electrically coupled to theoutput bump electrodes OBMP.

Here, points of difference between the semiconductor chip CHP2 in thepresent first embodiment shown in FIG. 4 and the general semiconductorchip CHP1 shown in FIG. 1 will be described. First, in the generalsemiconductor chip CHP1 shown in FIG. 1, the output bump electrodes OBMPare formed along the long side LS2 and in the lower layer that overlapsthe output bump electrode OBMP in a planar view, the output protectioncircuit 4 is formed. That is, the output protection circuit 4 isarranged along the long side LS2 similarly to the output bump electrodeOBMP. Then, at the center part of the semiconductor chip CHP1 adjacentto the output protection circuit 4, the SRAMs 2 a, 2 b and the controlpart 1 are formed. Specifically, the SRAMs 2 a, 2 b and the control part1 are arranged so as to stand side by side in the long-side direction.Subsequently, the input bump electrodes IBMP are formed along the longside LS1 in opposition to the long side LS2 of the semiconductor chipCHP1 and in the lower layer that overlaps the input bump electrode IBMPin a planar view, the input protection circuit 3 is formed. Because ofthis, the functional blocks that function as the LCD driver include theoutput protection circuit 4 formed along the long side LS2, the inputprotection circuit 3 formed along the long side LS1, and the SRAMs 2 a,2 b and the control part 1 formed at the center part between the outputprotection circuit 4 and the input protection circuit 3. In other words,in the semiconductor chip CHP1, if a region along the long side LS2 isdefined as an upper tier block, a region along the long side LS1 as alower tier block, and a region sandwiched by the upper tier block andthe lower tier block as a center block, in the general semiconductorchip CHP1, in the upper tier block, the output protection circuit 4 isformed and in the center block, the SRAMs 2 a, 2 b and the control part1 are formed. Then, in the lower tier block, the input protectioncircuit 3 is formed. Because of this, in the general LCD driver, thelength in the short-side direction is regulated by the output protectioncircuit 4 formed in the upper tier block, the SRAMs 2 a, 2 b and thecontrol part 1 formed in the center block, and the input protectioncircuit 3 formed in the lower tier block as a result.

In contrast to this, in the semiconductor chip CHP2 in the present firstembodiment shown in FIG. 4, along the long side LS2, the output bumpelectrodes OBMP are formed, and in the lower layer that overlaps theoutput bump electrode OBMP in a planar view, the output protectioncircuit 4 is formed. That is, similarly to the output bump electrodeOBMP, the output protection circuit 4 is arranged along the long sideLS2. Then, at the center part of the semiconductor chip CHP2 adjacent tothe output protection circuit 4, the SRAMs 2 a to 2 c, the control part1, and the input protection circuits 3 a to 3 c are formed. That is, inthe semiconductor chip CHP2 in the present first embodiment, in theupper tier block along the long side LS2, the output protection circuit4 is formed and in the center block adjacent to the upper tier block,the SRAMs 2 a to 2 c, the control part 1, and the input protectioncircuits 3 a to 3 c are formed. That is, in the semiconductor chip CHP1constituting the general LCD driver shown in FIG. 1, the outputprotection circuit 4, the SRAMs 2 a, 2 b, the control part 1, and theinput protection circuit 3 are arranged separately in the three tiers,that is, the upper tier block, the center block, and the lower tierblock, however, in the semiconductor chip CHP2 constituting the LCDdriver in the present first embodiment, the region is included, in whichthe output protection circuit 4, the SRAMs 2 a to 2 c, the control part1, and the input protection circuits 3 a to 3 c are arranged separatelyin the two tiers, that is, the upper tier block and the center block,and this is the point of difference. Here, if the region where thecontrol part 1 and the input protection circuit 3 c are arranged isfocused on, it seems that the output protection circuit 4, the controlpart 1, and the input protection circuit 3 c are arranged in threetiers, however, if it is assumed that the length in the short-sidedirection of the SRAMs 2 a to 2 c is regarded as the length in theshort-side direction of the center block, the total length in theshort-side direction of the control part 1 and the input protectioncircuit 3 c is shorter than the length in the short-side direction ofthe SRAMs 2 a to 2 c, and therefore, it can be thought that the controlpart 1 and the input protection circuit 3 c are formed substantially inthe range of the center block regulated by the length in the short-sidedirection of the SRAMs 2 a to 2 c. Because of this, in the present firstembodiment, the layout configuration shown in FIG. 4 is also expressedas that the output protection circuit 4, the SRAMs 2 a to 2 c, thecontrol part 1, and the input protection circuits 3 a to 3 c arearranged separately in the two tiers, that is, the upper tier block andthe center block. Alternatively, by taking into consideration the regionwhere the control part 1 and the input protection circuit 3 c arearranged, which can be regarded as a region including three separatetiers, it is possible to express the configuration in the present firstembodiment as that the output protection circuit 4, the SRAMs 2 a to 2c, the control part 1, and part of the input protection circuits 3 a to3 c are arranged separately in the two tiers, that is, the upper tierblock and the center block.

As described above, the semiconductor chip CHP2 constituting the LCDdriver in the present first embodiment is characterized in that theoutput protection circuit 4, the SRAMs 2 a to 2 c, the control part 1,and the input protection circuits 3 a to 3 c are arranged separately inthe two tiers, that is, the upper tier block and the center block,rather than arranged in the three tiers, that is, the upper tier block,the center block, and the lower tier block. In other words, the presentfirst embodiment is characterized in that the input protection circuits3 a to 3 c are arranged in part of the center block where the SRAMs 2 ato 2 c and the control part 1 are arranged instead of that the inputprotection circuits 3 a to 3 c are arranged in the lower tier block sothat they are arranged along the long side LS1. Due to this, accordingto the semiconductor chip CHP2 in the present first embodiment, it ispossible to reduce the length in the short-side direction. That is, inthe semiconductor chip CHP1 constituting the general LCD driver shown inFIG. 1, the upper tier block, the center block, and the lower tier blockare arranged along the short-side direction and the length in theshort-side direction is determined by the area occupied by the threetiers, that is, the upper tier block, the center block, and the lowertier block. In contrast to this, according to the semiconductor chipCHP2 in the present first embodiment shown in FIG. 4, along theshort-side direction, the upper tier block and the center block arearranged and the length in the short-side direction is determined by thearea occupied by the two tiers, that is, the upper tier block and thecenter block. That is, in the semiconductor chip CHP2 shown in FIG. 4,the lower tier block that exists in the semiconductor chip CHP1 shown inFIG. 1 does not exist. Because of this, it is possible to reduce thelength in the short-side direction by an amount that would be occupiedby the lower tier block that is no longer arranged. As a result of that,the semiconductor chip CHP2 in the present first embodiment exhibits aremarkable effect that the length in the short-side direction can bereduced.

In the present first embodiment, by devising the position of arrangementof the input protection circuits 3 a to 3 c, the length in theshort-side direction of the semiconductor chip CHP2 is reduced.Specifically, as shown in FIG. 4, at least some of the input protectioncircuits 3 a to 3 c are not arranged along the long side LS1, alongwhich the input bump electrodes IBMP are arranged side by side. Forexample, the input protection circuit 3 a is formed between the SRAM 2 aand the SRAM 2 b and the input protection circuits 3 b is formed betweenthe SRAM 2 b and the SRAM 2 c. Then, the input protection circuit 3 c isformed between the control part 1 and the long side LS1. As a result ofthat, not all of the input protection circuits 3 a to 3 c are formed inthe lower layer that overlaps the input bump electrode IBMP in a planarview. That is, in the present first embodiment, as shown in FIG. 4, inthe lower layer of the input bump electrode IBMP arranged along the longside LS1, the input protection circuits 3 a to 3 c and the SRAMs 2 a to2 c are formed as a result. Because of this, in the present firstembodiment, in the lower layer of part of the input bump electrodesIBMP, the input protection circuits 3 a to 3 c are arranged, and on theother hand, in the lower layer of the other part of the input bumpelectrodes IBMP of the input bump electrodes IBMP, the input protectioncircuits 3 a to 3 c are not arranged but the SRAMs 2 a to 2 c (internalcircuit) are arranged. In particular, in the present first embodiment,the number of part of the input bump electrodes IBMP in the lower layerof which the input protection circuits 3 a to 3 c are arranged issmaller than the number of the other part of the input bump electrodesIBMP in the lower layer of which the input protection circuits 3 a to 3c are not arranged.

The characteristic of the present first embodiment can be expresseddifferently from the above, such as that part of the input protectioncircuits 3 a, 3 b are disposed in an inner region sandwiched between aregion where the input bump electrodes IBMP are formed and a regionwhere the output bump electrodes OBMP are formed. It can be expressedfurther, such as that part of the input protection circuits 3 a to 3 care formed in a region that does not overlap the input bump electrodesIBMP in a planar view, or that part of the input protection circuits 3a, 3 b are formed in a region adjacent to the SRAMs 2 a to 2 c in thelong-side direction. Furthermore, it can be expressed, such as that partof the input protection circuits 3 a, 3 b electrically coupled to partof the input bump electrodes IBMP are disposed at a position thatoverlaps the part of the input bump electrodes in a planar view and theother input protection circuits of the input protection circuits 3 a, 3b electrically coupled to the other input bump electrodes of the inputbump electrodes IBMP are disposed at a position different from aposition that overlaps the other input bump electrodes in a planar view.

In the present first embodiment, the input protection circuit 3 a andthe input protection circuit 3 b are disposed between the SRAMs 2 a to 2c, however, there arises a problem whether there exists a space wherethe input protection circuit 3 a and the input protection circuit 3 bcan be disposed between the SRAMs 2 a to 2 c as described above. This isbecause it can be thought normally that the length in the long-sidedirection of the semiconductor chip CHP2 is determined so that no excessspace is left in order to make an attempt to reduce in size thesemiconductor chip CHP2. However, in actuality, it is possible to ensurea space into which the input protection circuit 3 a and the inputprotection circuit 3 b can be inserted between the SRAMs 2 a to 2 c. Thereason for that will be described below.

The length in the long-side direction of the semiconductor chip CHP2 isalso reduced as much as possible, however, the length in the long-sidedirection is regulated by the output bump electrodes OBMP arranged alongthe long side LS2. That is, the length in the long-side direction of thesemiconductor chip CHP2 is not regulated by the SRAMs 2 a to 2 c or thecontrol part 1 put side by side along the long-side direction but by thenumber of the output bump electrodes OBMP. For example, it can beconceived of reducing the formation region of the SRAMs 2 a to 2 c andthe control part 1 put side by side along the long-side direction asmuch as possible from the standpoint of the reduction in length in thelong-side direction of the semiconductor chip CHP2. Specifically, it canbe conceived of reducing the space between the SRAMs 2 a to 2 c and thecontrol part 1 as much as possible. However, even if the length in thelong-side direction of the semiconductor chip CHP2 is reduced by denselyarranging the formation regions of the SRAMs 2 a to 2 c and the controlpart 1 as described above, this attempt will be in vain if all of theoutput bump electrodes OBMP cannot be arranged along the long side LS2of the semiconductor chip CHP2. Because of this, it is necessary for thelength in the long-side direction of the semiconductor chip CHP2 to haveat least a length that allows arrangement of all of the output bumpelectrodes OBMP. That is, the length in the long-side direction of thesemiconductor chip CHP2 is determined from the standpoint of thepossibility of arrangement of all of the output bump electrodes OBMP.

At this time, there is a problem of, for example, the relationship inmagnitude between the length in the long-side direction of the SRAMs 2 ato 2 c and the control part 1 put side by side in the long-sidedirection and the total length of the output bump electrodes OBMParranged along the long side LS2, however, in actuality, the totallength of the output bump electrodes OBMP is greater than the length ofthe SRAMs 2 a to 2 c and the control part 1 put side by side. Because ofthis, if the length in the long-side direction of the semiconductor chipCHP2 is determined so that all of the output bump electrodes OBMP can bearranged, there exists an excess space in the region where the SRAMs 2 ato 2 c and the control part 1 are put side by side. Because of this, forexample, it is possible to ensure a space between the SRAMs 2 a to 2 cwhere the input protection circuit 3 a and the input protection circuit3 b are inserted. Because of this, in the present first embodiment, itis possible to reduce the length in the short-side direction of thesemiconductor chip CHP2 by, for example, inserting the input protectioncircuit 3 a and the input protection circuit 3 b between the SRAMs 2 ato 2 c.

Next, in the semiconductor chip CHP2, the output protection circuit 4exists in addition to the input protection circuits 3 a to 3 c. Theinput protection circuits 3 a to 3 c and the output protection circuit 4function as an electrostatic protection circuit that protects theinternal circuit against static electricity. Then, they function as thesame electrostatic protection circuit, and therefore, it can be thoughtthat the input protection circuits 3 a to 3 c and the output protectioncircuit 4 have the same configuration. Because of this, it can beconceived of inserting the output protection circuit 4 instead of theinput protection circuits 3 a, 3 b into the space created when the SRAMs2 a to 2 c and the control part 1 are put side by side in the long-sidedirection. In this case also, if all of the output protection circuits 4can be inserted into the excess space created between the SRAMs 2 a to 2c and the control part 1, it is possible to reduce the length in theshort-side direction of the semiconductor chip CHP2. However, in thepresent first embodiment, the arrangement of the output protectioncircuit 4 is not modified but only the arrangement of the inputprotection circuits 3 a to 3 c is modified. The reason for that will bedescribed below.

As shown in FIG. 4, the number of the output bump electrodes OBMP is byfar greater than that of the input bump electrodes IBMP. An outputsignal is output from each of the output bump electrodes OBMP, andtherefore, it is necessary to provide the output protection circuit 4for each of the output bump electrodes OBMP. Because of this, the numberof the output protection circuits 4 is also enormously great. On theother hand, the number of the input bump electrodes IBMP is smaller thanthat of the output bump electrodes OBMP and it is not necessary tocouple the input protection circuits 3 a to 3 c to all of the input bumpelectrodes IBMP. Of the input bump electrodes IBMP, the bump electrodesto which the input protection circuits 3 a to 3 c are coupled are onlythe bump electrodes to receive an input signal (input data). Because ofthis, the number of the input protection circuits 3 a to 3 c is smallercompared to that of the output protection circuits 4. This means thatthe area occupied by all of the input protection circuits 3 a to 3 c issmaller than that occupied by all of the output protection circuits 4.That is, the number of spaces into which the input protection circuits 3a to 3 c are inserted is smaller than that of spaces into which theoutput protection circuits 4 are inserted.

Here, the space created when the SRAMs 2 a to 2 c and the control part 1are put side by side in the long-side direction is not so large. Thatis, the space created when the SRAMs 2 a to 2 c and the control part 1are put side by side in the long-side direction is not large enough toallow the insertion of all of the output protection circuits 4. In otherwords, it is not possible to make large enough the space created whenthe SRAMs 2 a to 2 c and the control part 1 are put side by side in thelong-side direction, and therefore, instead of the output protectioncircuits 4, the input protection circuits 3 a to 3 c are inserted intothe space described above.

Subsequently, a second characteristic point in the present firstembodiment will be described. The second characteristic point in thepresent first embodiment is that the input protection circuits 3 a to 3c are dispersed in the long-side direction of the semiconductor chipsCHP2 rather than concentrated at one part, as shown in FIG. 4. Forexample, it can be conceived of putting together at one part the spacescreated when the SRAMs 2 a to 2 c and the control part 1 are put side byside in the long-side direction and arranging the input protectioncircuits 3 a to 3 c in the spaces put together at one part. In thiscase, there is exhibited an effect that the size of the semiconductorchip can be reduced. However, the arrangement in which the inputprotection circuits 3 a to 3 c are dispersed as shown in FIG. 4 is moreeffective and the reason for this will be described below.

For example, it is necessary to electrically couple the input protectioncircuits 3 a to 3 c between the input bump electrode IBMP and theinternal circuit. At this time, for example, in the semiconductor chipCHP1 constituting the general LCD driver shown in FIG. 1, the inputprotection circuit 3 is formed in the lower layer that overlaps theinput bump electrode IBMP in a planar view, and therefore, it ispossible to electrically couple the input bump electrode IBMP and theinput protection circuit 3 using a multilayer wiring that runs from theinput bump electrode IBMP toward the lower layer. This means that thereis no need to use a routing wiring that extends in the direction of theplane of the semiconductor chip CHP1 in order to couple the input bumpelectrode IBMP to the input protection circuit 3.

In the present first embodiment, however, in the region that does notoverlap the input bump electrode IBMP in a planar view, the inputprotection circuits 3 a to 3 c are formed as a result. Because of this,it is necessary to use a routing wiring that extends in the direction ofthe plane of the semiconductor chip CHP2 in order to couple the inputbump electrodes IBMP and the input protection circuits 3 a to 3 c in thepresent first embodiment. Based on the assumption of the above, if theinput protection circuits 3 a to 3 c are arranged together at one part,it is necessary to couple the input protection circuits 3 a to 3 carranged together and the input bump electrodes IBMP arranged in thelong-side direction of the semiconductor chip CHP2 using a routingwiring that extends in the direction of the plane of the semiconductorchip CHP2. In this case, if the input protection circuits 3 a to 3 c areconcentrated at one part, the layout configuration of the routing wiringwill become complicated.

Because of this, in the present first embodiment, on the assumption thatthe input protection circuits 3 a to 3 c are formed in a region thatdoes not overlap the input bump electrodes IBMP in a planar view, theinput protection circuits 3 a to 3 c are arranged dispersedly. Due tothis, it is possible to couple each of the input bump electrodes IBMParranged in the long-side direction of the semiconductor chip CHP2 tothe input protection circuit having the shortest distance from the inputbump electrode IBMP, among the input protection circuits 3 a to 3 carranged dispersedly. This means that it is possible to reduce thelength of a routing wiring used to couple the input bump electrode IBMPand the input protection circuits 3 a to 3 c and to simplify the layoutconfiguration of the routing wiring more than that in the case where theinput protection circuits 3 a to 3 c are concentrated at one part.Because of this, according to the present first embodiment, due to thefirst characteristic point that the input protection circuits 3 a to 3 care arranged in the space created when the SRAMs 2 a to 2 c and thecontrol part 1 are put side by side in the long-side direction, it ispossible to reduce the length in the short-side direction of thesemiconductor chip CHP2 constituting the LCD driver. Then, according tothe first characteristic point, the input protection circuits 3 a to 3 care formed in the region that does not overlap the input bump electrodesIBMP in a planar view, and further, due to the second characteristicpoint that the input protection circuits 3 a to 3 c are arrangeddispersedly in the long-side direction of the semiconductor chip CHP2rather than concentrated at one part, it is possible to simplify thelayout configuration of the routing wiring used to electrically couplethe input bump electrodes IBMP and the input protection circuits 3 a to3 c.

Although it is desirable to comprise the first characteristic point andthe second characteristic point as in the present first embodiment, itis possible to sufficiently achieve the object of the present inventionto reduce the length in the short-side direction of the semiconductorchip CHP2 even with the configuration in which only the firstcharacteristic point is comprised.

According to the semiconductor chip CHP2 in the present firstembodiment, it is possible to reduce the length in the short-sidedirection of the semiconductor chip CHP2, and this will be describednext using an enlarged view. FIG. 5 is an enlarged view of a region inthe vicinity of the long side LS1 of the semiconductor chip CHP1constituting a general LCD driver. In FIG. 5, X direction represents thelong-side direction in which the long side LS1 of the semiconductor chipCHP1 extends and Y direction represents the short-side direction of thesemiconductor chip CHP1. As shown in FIG. 5, along the long side LS1 ofthe semiconductor chip CHP1, two input bump electrodes, IBMP1 and IBMP2,are arranged side by side. Then, in the lower layer of the input bumpelectrode IBMP1, uppermost layer wirings TM1, TM3 and TM4 are formed.Similarly, in the lower layer of the input bump electrode IBMP2, anuppermost layer wiring TM2 and the uppermost layer wirings TM3, TM4 areformed. At this time, the uppermost layer wiring TM1 is formed only inthe lower layer of the input bump electrode IBMP1 and the uppermostlayer wiring TM2 is formed only in the lower layer of the input bumpelectrode IBMP2. On the other hand, the uppermost layer wiring TM3 andthe uppermost layer wiring TM4 are formed across the lower layers of theinput bump electrode IBMP1 and the input bump electrode IBMP2 and extendin the long-side direction (X direction).

The input bump electrode IBMP1 and the uppermost layer wiring TM1 areelectrically coupled by filling an opening CNT1 with a conductivematerial. Then, the uppermost layer wiring TM1 is coupled to an inputprotection circuit 3A via a multilayer wiring formed in the lower layer.Similarly, the input bump electrode IBMP2 and the uppermost layer wiringTM2 are electrically coupled by filling an opening CNT2 with aconductive material. Then, the uppermost layer wiring TM2 is coupled toan input protection circuit 3B via a multilayer wiring formed in thelower layer. In the semiconductor chip CHP1 constituting a general LCDdriver as described above, in the lower layers of the input bumpelectrodes IBMP1, IBMP2, the input protection circuits 3A, 3B areformed. Because of this, the internal circuit IU is formed at an innerside of the input bump electrodes IBMP1, IBMP2 (region farther from thelong side LS1) so as not to overlap the input bump electrodes IBMP1,IBMP2 in a planar view. Because of this, the distance between theinternal circuit IU and the long side LS1 of the semiconductor chip CHP1is distance Y1.

In contrast to this, FIG. 6 is an enlarged view of a region in thevicinity of the long side LS1 of the semiconductor chip CHP2, which isthe LCD driver in the present first embodiment. In FIG. 6, the Xdirection represents the long-side direction in which the long side LS1of the semiconductor chip CHP2 extends and the Y direction representsthe short-side direction of the semiconductor chip CHP2. As shown inFIG. 6, along the long side LS1 of the semiconductor chip CHP2, twoinput bump electrodes, IBMP1 and IBMP2, are arranged side by side. Then,in the lower layer of the input bump electrode IBMP1, the uppermostlayer wirings TM1, TM3, TM4 are formed. Similarly, in the lower layer ofthe input bump electrode IBMP2, the uppermost layer wirings TM2, TM3,TM4 are formed. At this time, the uppermost layer wiring TM1 is formedonly in the lower layer of the input bump electrode IBMP1 and theuppermost layer wiring TM2 is formed only in the lower layer of theinput bump electrode IBMP2. On the other hand, the uppermost layerwiring TM3 and the uppermost layer wiring TM4 are formed across thelower layers of the input bump electrode IBMP1 and the input bumpelectrode IBMP2 and extend in the long-side direction (X direction).

The input bump electrode IBMP1 and the uppermost layer wiring TM1 areelectrically coupled by filling the opening CNT1 with a conductivematerial, however, in the present first embodiment, no input protectioncircuit is formed in the lower layer of the uppermost layer wiring TM1.Similarly, the input bump electrode IBMP2 and the uppermost layer wiringTM2 are electrically coupled by filling the opening CNT2 with aconductive material, however, in the present first embodiment, no inputprotection circuit is formed in the lower layer of the uppermost layerwiring TM2. In the present first embodiment, the input protectioncircuit (not shown schematically in FIG. 6) is formed in a region thatdoes not overlap the input bump electrodes IBMP1, IBMP2 in a planarview. As described above, in the semiconductor chip CHP2 in the presentfirst embodiment, no input protection circuit is formed in the lowerlayer of the input bump electrodes IBMP1, IBMP2, and therefore, part ofthe internal circuit IU is formed in the lower layer that overlaps theinput bump electrodes IBMP1, IBMP2 in a planar view. As a result ofthis, the distance between the internal circuit IU and the long side LS1of the semiconductor chip CHP2 is distance Y2.

Here, from the comparison between the distance Y1 shown in FIG. 5 andthe distance Y2 shown in FIG. 6, it is known that the distance Y2 shownin FIG. 6 is smaller than the distance Y1 shown in FIG. 5. This meansthat it is possible to reduce the length in the short-side directionmore in the semiconductor chip CHP2 shown in FIG. 6 than in thesemiconductor chip CHP1 shown in FIG. 5. That is, according to thesemiconductor chip CHP2 in the present first embodiment, it is knownthat the length in the short-side direction can be reduced more thanthat in the general semiconductor chip CHP1.

The part of the input bump electrode IBMP1 in FIG. 6 corresponds to FIG.13 in a fifth embodiment, to be described later, and a section view cutalong A-A line in FIG. 13 corresponds to FIG. 14 in the fifthembodiment, to be described later. The device structure in the presentfirst embodiment will be described in more detail using the section viewin the fifth embodiment, to be described later.

In the present first embodiment, the example is shown, in which theuppermost layer wirings TM3, TM4 pass through the lower layers of theinput bump electrodes IBMP1, IBMP2, however, this is not limited, andthe same effect can be obtained when at least one or more uppermostlayer wirings pass through. This also applies to the followingembodiments.

Second Embodiment

In the first embodiment described above, the configuration is described,in which, for example, as shown in FIG. 4, while the input protectioncircuits 3 a to 3 c are arranged in the lower layer of part of the inputbump electrodes IBMP, the input protection circuits 3 a to 3 c are notarranged but the SRAMs 2 a to 2 c (internal circuit) are arranged in thelower layer of the other input bump electrodes IBMP of the input bumpelectrodes IBMP.

In a second embodiment, an example will be described, where no inputprotection circuit is formed in the lower layer of all of the input bumpelectrodes IBMP.

FIG. 7 is a diagram showing a layout configuration of the semiconductorchip CHP2 in the present second embodiment. In FIG. 7, similarly to thesemiconductor chip CHP2 in the above-mentioned first embodiment shown inFIG. 4, the semiconductor chip CHP2 in the present second embodiment isin the form of a rectangle having a pair of the short side SS1 and theshort side SS2 and a pair of the long side LS1 and the long side LS2.Then, along the long side LS1, the input bump electrodes IBMP arearranged and along the long side LS2, the output bump electrodes OBMPare arranged. Further, the semiconductor chip CHP2 in the present secondembodiment has the control part 1, the SRAMs 2 a, 2 b, the inputprotection circuits 3 a, 3 b, and the output protection circuit 4.

At this time, in the present second embodiment also, the inputprotection circuits 3 a, 3 b are formed in the space created when theSRAMs 2 a, 2 b and the control part 1 are put side by side in thelong-side direction. However, the input protection circuits 3 a, 3 bformed in the space are formed so as not to overlap the input bumpelectrodes IBMP arranged along the long side LS1. That is, in thepresent second embodiment, unlike the above-mentioned first embodiment,no input protection circuits are formed in the lower layer of any of theinput bump electrodes IBMP.

It is also possible to configure the semiconductor chip CHP2constituting an LCD driver as in the present second embodiment. In thecase of the configuration as in the present second embodiment also, dueto the first characteristic point that the input protection circuits 3a, 3 b are arranged in the space created when the SRAMs 2 a, 2 b and thecontrol part 1 are put side by side in the long-side direction, it ispossible to reduce the length in the short-side direction of thesemiconductor chip CHP2 constituting the LCD driver. Then, according tothe first characteristic point, the input protection circuits 3 a, 3 bare formed in a region that does not overlap the input bump electrodesIBMP in a planar view, and further, due to the second characteristicpoint that the input protection circuits 3 a, 3 b are arrangeddispersedly in the long-side direction of the semiconductor chip CHP2rather than concentrated at one position, it is possible to simplify thelayout configuration of the routing wirings that electrically couple theinput bump electrode IBMP and the input protection circuits 3 a, 3 b.That is, with the layout configuration in the present second embodiment,it is also possible to obtain the same effects as those obtained in theabove-mentioned first embodiment.

Third Embodiment

In the above-mentioned first embodiment, as shown in FIG. 4, accordingto the first characteristic point that the input protection circuits 3 ato 3 c are arranged in the space created when the SRAMs 2 a to 2 c andthe control part 1 are put side by side in the long-side direction, thelength in the short-side direction of the semiconductor chip CHP2constituting the LCD driver is reduced. Because of this, in theabove-mentioned first embodiment, at least some of the input protectioncircuits 3 a to 3 c are formed in the region that does not overlap theinput bump electrodes IBMP in a planar view as a result. Because ofthis, in the above-mentioned first embodiment, it is necessary to use arouting wiring that extends in the direction of the plane of thesemiconductor chip CHP2 in order to electrically couple the input bumpelectrodes IBMP and the input protection circuits 3 a to 3 c. In thiscase, the wiring layout of the semiconductor chip CHP2 will becomecomplicated unless the layout configuration of the routing wirings isdevised.

Because of this, in the present third embodiment, a technical idea toefficiently make use of the routing wiring that extends in the directionof the plane of the semiconductor chip CHP2 will be described. That is,in the present third embodiment, when the input protection circuits 3 ato 3 c are formed in a region that does not overlap the input bumpelectrodes IBMP in a planar view, the wiring layout to electricallycouple the input bump electrodes IBMP and the input protection circuits3 a to 3 c is devised. A plurality of devices in the present thirdembodiment will be described below.

First, a first device point in the present third embodiment will bedescribed. FIG. 8 is a diagram for illustrating the first device pointin the present third embodiment. In FIG. 8, the X direction representsthe long-side direction in which the long side LS1 of the semiconductorchip CHP2 extends and the Y direction represents the short-sidedirection of the semiconductor chip CHP2. As shown in FIG. 8, threeinput bump electrodes, IBMP1, IBMP2 and IBMP3, are arranged side by sidealong the long side LS1 of the semiconductor chip CHP2.

Here, the first device point in the present third embodiment is, forexample, a method of coupling the uppermost layer wiring TM1electrically coupled to the input bump electrodes IBMP1 to IBMP3 andalso coupled to the input protection circuit 3, and the input bumpelectrodes IBMP1 to IBMP3. Specifically, as shown in FIG. 8, the inputbump electrode IBMP1 and the uppermost layer wiring TM1 are coupled viaa conductive material filled in the opening CNT1 and the input bumpelectrode IBMP2 and the uppermost layer wiring TM1 are coupled via aconductive material filled in the opening CNT2. Then, the input bumpelectrode IBMP3 and the uppermost layer wiring TM1 are coupled via aconductive material filled in the opening CNT3. At this time, the firstdevice point lies in that the positions where the openings CNT1 to CNT3are formed are different.

That is, there may be a case where another uppermost layer wiring otherthan the uppermost layer wiring TM1 is arranged in the lower layer ofthe input bump electrodes IBMP1 to IBMP3. In this case, if the positionswhere the openings CNT1 to CNT3 are formed for the input bump electrodesIBMP1 to IBMP3 are the same, the arrangement of another uppermost layerwiring may be blocked. Because of this, according to the first devicepoint in the present third embodiment shown in FIG. 8, the positionwhere the opening CNT1 is formed for the input bump electrode IBMP1, theposition where the opening CNT2 is formed for the input bump electrodeIBMP2, and the position where the opening CNT3 is formed for the inputbump electrode IBMP3 are made to differ from one another. Due to this,it is possible to form the uppermost layer wiring TM1 that extendsthrough the lower layer of the input bump electrodes IBMP1 to IBMP3 andis coupled to the input protection circuit 3 without blocking anotheruppermost layer wiring to be arranged in the lower layer of the inputbump electrodes IBMP1 to IBMP3.

For example, as shown in FIG. 8, the position where the opening CNT1 tobe coupled to the input bump electrode IBMP1 is formed is closest to thelong side LS1 of the semiconductor chip CHP2 and the position where theopening CNT3 to be coupled to the input bump electrode IBMP3 is formedis farthest from the long side LS1 of the semiconductor chip CHP2.

In FIG. 8, the input bump electrodes IBMP1 to IBMP3 are coupled by theuppermost layer wiring TM1, and therefore, the input bump electrodesIBMP1 to IBMP3 have the same function. As such a bump electrode, mentionis made, for example, of the bump electrode for power supply (Vcc, Vdd).Further, this also applies when the input bump electrodes IBMP2, IBMP3are used as a dummy bump electrode. That is, when the bump electrodeshaving the same purpose are adjacent to each other, it is possible tomake the bump electrodes common to each other by using the uppermostlayer wiring TM1 as shown in FIG. 8.

Subsequently, a second device point in the present third embodiment willbe described. FIG. 9 is a diagram for illustrating the second devicepoint in the present third embodiment. In FIG. 9, the X directionrepresents the long-side direction in which the long side LS1 of thesemiconductor chip CHP2 extends and the Y direction represents theshort-side direction of the semiconductor chip CHP2. As shown in FIG. 9,the three input bump electrodes, IBMP1, IBMP2 and IBMP3, are arrangedside by side along the long side LS1 of the semiconductor chip CHP2.Then, in the lower layer of the input bump electrodes IBMP1 to IBMP3,the uppermost layer wirings TM1 to TM3 are arranged and these uppermostlayer wirings TM1 to TM3 are coupled to the input protection circuit 3.

Here, the input bump electrode IBMP1 and the uppermost layer wiring TM1are coupled via a conductive material filled in the opening CNT1 and theinput bump electrode IBMP2 and the uppermost layer wiring TM2 arecoupled via a conductive material filled in the opening CNT2. Further,the input bump electrode IBMP3 and the uppermost layer wiring TM3 arecoupled via a conductive material filled in the opening CNT3. This isthe second device point in the present third embodiment.

That is, according to the second device point in the present thirdembodiment, the uppermost layer wirings TM1 to TM3 different from oneanother are coupled to the input bump electrodes IBMP1 to IBMP3different from one another, respectively, and the positions where theopenings CNT1 to CNT3 for the input bump electrodes IBMP1 to IBMP3 areformed are made to differ from one another. By forming the respectiveopenings CNT1 to CNT3 to be coupled to the input bump electrodes IBMP1to IBMP3 different from one another at different positions as describedabove, it is possible to efficiently couple the uppermost layer wiringsTM1 to TM3 and the input bump electrodes IBMP1 to IBMP3, respectively,without the need to modify the wiring layout of the uppermost layerwirings TM1 to TM3.

Specifically, due to the second device point in the present thirdembodiment, the uppermost layer wirings include the uppermost layerwiring TM1 which is coupled to the input bump electrode IBMP1 via theopening CNT1, and passes under the input bump electrode IBMP2, and whichis not coupled to the input bump electrode IBMP2, and the uppermostlayer wiring TM2 which is coupled to the input bump electrode IBMP2 viathe opening CNT2, and passes under the input bump electrode IBMP1, andwhich is not coupled to the input bump electrode IBMP1. Further, theuppermost layer wirings also include the uppermost layer wiring TM3which passes under the input bump electrode IBMP1 and the input bumpelectrode IBMP2 and is not coupled to the input bump electrode IBMP1 orthe input bump electrode IBMP2.

Next, a third device point in the present third embodiment will bedescribed. FIG. 10 is a diagram for illustrating the third device pointin the present third embodiment. In FIG. 10, the X direction representsthe long-side direction in which the long side LS1 of the semiconductorchip CHP2 extends and the Y direction represents the short-sidedirection of the semiconductor chip CHP2. As shown in FIG. 10, the threeinput bump electrodes, IBMP1, IBMP2 and IBMP3, are arranged side by sidealong the long side LS1 of the semiconductor chip CHP2. Then, in thelower layer of the input bump electrodes IBMP1 to IBMP3, the uppermostlayer wirings TM1 to TM3 are arranged and the uppermost layer wiring TM3of these uppermost layer wirings TM1 to TM3 is coupled to the inputprotection circuit 3.

Here, the input bump electrode IBMP1 and the uppermost layer wiring TM1are coupled via a conductive material filled in the opening CNT1 and theinput bump electrode IBMP2 and the uppermost layer wiring TM2 arecoupled via a conductive material filled in the opening CNT2. Then, theinput bump electrode IBMP3 and the uppermost layer wiring TM3 arecoupled via a conductive material filled in an opening CNT3 b. Further,the input bump electrode IBMP3 is also coupled to the uppermost layerwiring TM1 via a conductive material filled in an opening CNT3 a. Thatis, the third device point in the present third embodiment lies in that,for example, the coupling of an input bump electrode to a plurality ofdifferent uppermost layer wirings like the input bump electrode IBMP3that is coupled to the plurality of the different uppermost layerwirings TM1, TM3. Specifically, to the input bump electrode IBMP3, twoopenings, CNT3 a and CNT3 b, are coupled. Then, the input bump electrodeIBMP3 and the uppermost layer wiring TM1 are coupled via a conductivematerial filled in the opening CNT3 a and the input bump electrode IBMP3and the uppermost layer wiring TM3 are coupled via a conductive materialfilled in the opening CNT3 b.

That is, the third device point in the present third embodiment lies inthat the input bump electrode IBMP3 is caused to have a capability ofcoupling the uppermost layer wiring TM1 and the uppermost layer wiringTM3. That is, in the third device point, the input bump electrode IBMP3functions as a wiring to couple the uppermost layer wiring TM1 and theuppermost layer wiring TM3. Due to this, it is no longer necessary toform another wiring to couple the uppermost layer wiring TM1 and theuppermost layer wiring TM3, and therefore, it is possible to make anattempt to simplify the wiring layout.

Incidentally, it is possible to adjust the configuration so that theinput bump electrode (the input bump electrodes IBMP1, IBMP2) to becoupled to one opening and the input bump electrode (the input bumpelectrode IBMP3) to be coupled to a plurality of openings coexist inaccordance with the wiring layout without the need to provide aplurality of openings to all of the input bump electrodes IBMP1 to IBMP3as shown in FIG. 10. Further, in FIG. 10, the configuration is suchthat, for example, the input bump electrode IBMP3 is coupled to the twoopenings CNT3 a, CNT3 b, however, this is not limited, and such aconfiguration in which the input bump electrode IBMP3 is coupled tothree or more openings may be accepted.

As described above, in the present third embodiment, the first devicepoint to the third device point are applied to the wiring layout toelectrically couple the input bump electrodes IBMP and the inputprotection circuits 3 a to 3 c. An example of a wiring layout thatemploys the first device point to the third device point will bedescribed below. FIG. 11 is a diagram showing an example of a wiringlayout in the present third embodiment. In FIG. 11, the X directionrepresents the long-side direction in which the long side LS1 of thesemiconductor chip CHP2 extends and the Y direction represents theshort-side direction of the semiconductor chip CHP2. As shown in FIG.11, along the long side LS1 of the semiconductor chip CHP2, five inputbump electrodes, that is, the input bump electrodes IBMP1 to IBMP3 andinput bump electrodes IBMP4, IBMP5 are arranged side by side. Then, inthe lower layer of the input bump electrodes IBMP1 to IBMP5, uppermostlayer wirings TM1 a to TM3 b are arranged and the uppermost layer wiringTM2 a of these uppermost layer wirings TM1 a to TM3 b is coupled to theinput protection circuit 3.

First, in the lower layer of the input bump electrode IBMP1, theuppermost layer wirings TM1 a, TM2 a, TM3 a are arranged and the inputbump electrode IBMP1 is electrically coupled to the uppermost layerwiring TM1 a via a conductive material filled in the opening CNT1.

Next, in the lower layer of the input bump electrode IBMP2, theuppermost layer wirings TM1 b, TM2 a, TM3 a are arranged. Then, theinput bump electrode IBMP2 is coupled to an opening CNT2 a and anopening CNT2 b, and via a conductive material filled in the opening CNT2a, the input bump electrode IBMP2 is also electrically coupled to theuppermost layer wiring TM1 b and at the same time, via a conductivematerial filled in the opening CNT2 b, the input bump electrode IBMP2 iselectrically coupled to the uppermost layer wiring TM3 a. That is, theinput bump electrode IBMP2 is coupled to the two different uppermostlayer wirings TM1 b, TM3 a and the third device point is used in theconfiguration of the input bump electrode IBMP2.

Subsequently, in the lower layer of the input bump electrode IBMP3, theuppermost layer wirings TM1 b, TM2 a are arranged and the input bumpelectrode IBMP3 is electrically coupled to the uppermost layer wiringTM2 a via a conductive material filled in the opening CNT3. Here, theinput bump electrode IBMP1 and the input bump electrode IBMP3 arefocused on. Then, the position of the opening CNT1 coupled to the inputbump electrode IBMP1 is different from the position of the opening CNT3coupled to the input bump electrode IBMP3 and the uppermost layer wiringTM1 a to be coupled to the input bump electrode IBMP1 and the uppermostlayer wiring TM2 a to be coupled to the input bump electrode IBMP3 aredifferent. That is, in the configuration of the input bump electrodeIBMP1 and the input bump electrode IBMP3, the second device point in thepresent third embodiment is used.

Next, in the lower layer of the input bump electrode IBMP4, theuppermost layer wirings TM1 b, TM2 b, TM2 a are arranged and the inputbump electrode IBMP4 is coupled to the uppermost layer wiring TM2 b viaa conductive material filled in an opening CNT4 a and coupled to theuppermost layer wiring TM2 a via a conductive material filled in anopening CNT4 b. Therefore, in the configuration of the input bumpelectrode IBMP4 also, the third device point in the present thirdembodiment is used. Further, the input bump electrode IBMP3 and theinput bump electrode IBMP4 are focused on. Then, the input bumpelectrode IBMP3 and the input bump electrode IBMP4 are coupled to thesame uppermost layer wiring TM2 a and the position where the openingCNT3 for the input bump electrode IBMP3 is formed is different from theposition where the opening CNT4 b for the input bump electrode IBMP4 isformed. Therefore, the first device point in the present thirdembodiment is used in this configuration as a result.

Subsequently, in the lower layer of the input bump electrode IBMP5, theuppermost layer wirings TM1 b, TM2 b, TM3 b are arranged and the inputbump electrode IBMP5 is electrically coupled to the uppermost layerwiring TM3 b via a conductive material filled in an opening CNT5. Thewiring layout example shown in FIG. 11 is configured as described aboveand it can be seen that the wiring layout is made using the first devicepoint to the third device point in the present third embodiment. Bymaking the wiring layout as described above, it is possible toefficiently arrange the uppermost layer wirings TM1 a to TM3 b for theinput bump electrodes IBMP1 to IBMP5, and therefore, it is possible tomake an attempt to simplify the wiring layout.

The technique disclosed in the present third embodiment is alsoeffective when forming the input protection circuits 3 a to 3 c in aregion that overlaps the input bump electrodes IBMP in a planar view aswith the prior art. Then, it is obviously possible to obtain the sameeffects also when using the first embodiment and the second embodimentdescribed above in combination.

Fourth Embodiment

In a fourth embodiment, an example will be described, in which the formof the input bump electrode and the form of the output bump electrodeare not the same but made to differ in size from each other.

The technical idea described in the above-mentioned third embodimentrelates to the coupling configuration between the input bump electrodeand the uppermost layer wiring and the effective use of the first devicepoint to the third device point described in the above-mentioned thirdembodiment is based on the assumption that the uppermost layer wiringsare arranged in the lower layer of the input bump electrode. Taking intoconsideration the assumption, in the present fourth embodiment,attention is focused on the point that the first device point to thethird device point in the above-mentioned third embodiment become a moreuseful technique as the number of uppermost layer wirings to be arrangedin the lower layer of the input bump electrode increases. Because ofthis, in the present fourth embodiment, the configuration of the inputbump electrode is devised in order to make use of the first device pointto the third device point in the above-mentioned third embodiment moreeffectively. A technical idea in the present fourth embodiment will bedescribed below.

FIG. 12 is an enlarged view showing a configuration of the semiconductorchip CHP2 constituting an LCD driver. In FIG. 12, the X directionrepresents the long-side direction in which the long sides LS1, LS2extend and the Y direction represents the short-side direction. As shownin FIG. 12, along the long side LS1, a plurality of input bumpelectrodes IBMP is arranged and along the other long side LS2 arrangedat a position in opposition to the long side LS1 along which the inputbump electrodes IBMP are arranged, a plurality of output bump electrodesOBMP is arranged. While the input bump electrodes IBMP are arrangedlinearly along the long side LS1, the output bump electrodes OBMP arearranged along the long side LS2 in two rows in a staggered manner.Because of this, the number of the output bump electrodes OBMP isgreater than that of the input bump electrodes IBMP.

The characteristic in the present fourth embodiment lies in that thesize of the input bump electrode IBMP is not the same as that of theoutput bump electrode OBMP but greater than that of the output bumpelectrode OBMP. More specifically, when the length in the short-sidedirection of the input bump electrode IBMP is assumed to be a and thelength in the short-side direction of the output bump electrode OBMP b,the length a of the input bump electrode IBMP is greater than the lengthb of the output bump electrode OBMP. The reason for thus increasing thesize of the input bump electrode IBMP is as follows.

That is, making greater the length in the short-side direction of theinput bump electrode IBMP means that the number of uppermost layerwirings to be arranged in the lower layer that overlaps the input bumpelectrode IBMP in a planar view can be increased. That is, by makinggreater the length in the short-side direction of the input bumpelectrode IBMP, the number of uppermost layer wirings that pass throughthe lower layer of the input bump electrode IBMP and extend in thedirection of the long side LS1 is increased. This means that the numberof uppermost layer wirings that pass through the lower layer of theinput bump electrodes IBMP arranged along the long side LS1 is increasedand as a result of that, the degree of freedom in coupling the inputbump electrodes IBMP by uppermost layer wirings is increased. Further,that the number of uppermost layer wirings that pass through the lowerlayer of the input bump electrodes IBMP increases means that thepotential to effectively make use of the first device point to the thirddevice point described in the above-mentioned third embodimentincreases. Because of this, according to the present fourth embodiment,by employing the characteristic configuration in which the length a ofthe input bump electrode IBMP is made greater than the length b of theoutput bump electrode OBMP, a remarkable effect is exhibited that thedegree of freedom in wiring layout is increased.

As described above, the present fourth embodiment employs thecharacteristic configuration in which the length a of the input bumpelectrode IBMP is made greater than the length b of the output bumpelectrode OBMP from the standpoint that the first device point to thethird device point in the above-mentioned third embodiment are made useof effectively by increasing the degree of freedom in wiring layout.That is, the plane area of the input bump electrode IBMP is made greaterthan that of the output bump electrode OBMP. By employing thecharacteristic configuration in the present fourth embodiment, secondaryeffects as shown below are also exhibited. The secondary effects will bedescribed.

For example, a case is considered, where the size of the input bumpelectrode IBMP and the size of the output bump electrode OBMP are thesame. In this case, the number of the input bump electrodes IBMP issmaller than that of the output bump electrodes OBMP, and therefore, thetotal area of the input bump electrodes IBMP is smaller than that of theoutput bump electrodes OBMP.

The input bump electrode IBMP and the output bump electrode OBMP formedin the semiconductor chip CHP2 function as a coupling terminal whenmounting the semiconductor chip CHP2, which is an LCD driver, over theglass substrate of a liquid crystal display device. At this time, thatthe total area of the input bump electrode IBMP is smaller than that ofthe output bump electrode OBMP means that the joint area on the side ofthe input bump electrode IBMP is smaller than that on the side of theoutput bump electrode OBMP. Because of this, the joint area along thelong side LS1 of the semiconductor chip CHP2 (total area of the inputbump electrode IBMP) and that along the long side LS2 of thesemiconductor chip CHP2 (total area of the output bump electrode OBMP)are different. As a result of that, when mounting the semiconductor chipCHP2 over the glass substrate, the balance between the joint strength atthe long side LS1 of the semiconductor chip CHP2 and that at the longside LS2 of the semiconductor chip CHP2 is lost and there arises apossibility that the joint strength between the semiconductor chip CHP2and the glass substrate is reduced.

In contrast to this, a case is considered, where the characteristicconfiguration in which the length a of the input bump electrode IBMP ismade greater than the length b of the output bump electrode OBMP isemployed as in the present fourth embodiment. In this case, the numberof the input bump electrodes IBMP is smaller than that of the outputbump electrodes OBMP, however, the size of one input bump electrode IBMPis greater than that of one output bump electrode OBMP. Consequently,the difference between the total area of the input bump electrodes IBMPand that of the output bump electrodes OBMP becomes smaller compared tothe case where the size of the input bump electrode IBMP and that of theoutput bump electrode OBMP are the same in dimensions. That is,according to the characteristic configuration in the present fourthembodiment, it is possible to make smaller the difference between thejoint area on the side of the input bump electrode IBMP and that on theside of the output bump electrode OBMP. As a result of that, theimbalance between the joint strength at the long side LS1 of thesemiconductor chip CHP2 and that at the long side LS2 of thesemiconductor chip CHP2 is relaxed when mounting the semiconductor chipCHP2 over the glass substrate, and therefore, the joint strength betweenthe semiconductor chip CHP2 and the glass substrate is increased.

In the present fourth embodiment, the length in the Y direction(short-side direction of the semiconductor chip CHP2) is illustrated,however as to the length in the X direction (long-side direction of thesemiconductor chip CHP2), it is desirable to make the same the length ofthe input bump electrode IBMP and that of the output bump electrodeOBMP, or to make greater the length of the input bump electrode IBMPthan that of the output bump electrode OBMP.

As described above, according to the characteristic configuration in thepresent fourth embodiment, it is possible to obtain the effect that thejoint strength between the semiconductor chip CHP2 and the glasssubstrate is increased as well as the effect that the degree of freedomin wiring layout is increased.

The technique disclosed in the present fourth embodiment is not limitedto the case in the third embodiment described above and can also beapplied to the first and second embodiments described above.

Fifth Embodiment

In a fifth embodiment, a device structure formed in the lower layer ofthe input bump electrode will be described. FIG. 13 is a diagram showingone input bump electrode IBMP1. In FIG. 13, the direction in which thelong side LS1 of the semiconductor chip CHP2 extends is referred to asthe X direction and the short-side direction of the semiconductor chipCHP2 is referred to as the Y direction. As shown in FIG. 13, the inputbump electrode IBMP1 is in the form of a rectangle and in the lowerlayer of the input bump electrode IBMP1, the three uppermost layerwirings TM1 to TM3 are arranged. The input bump electrode IBMP1 iselectrically coupled to the uppermost layer wiring TM1 via a conductivematerial filled in the opening CNT1. A device structure formed in thelower layer of the input bump electrode IBMP1 thus configured will bedescribed with reference to FIG. 14.

FIG. 14 is a section view cut along A-A line in FIG. 13, a section viewshowing a configuration of a semiconductor device in the present fifthembodiment. In the present fifth embodiment, for example, as shown inFIG. 4 in the above-mentioned first embodiment, the internal circuit(for example, SRAMs 2 a to 2 c) is formed in the lower layer of theinput bump electrode IBMP. Consequently, in the semiconductor substratein the lower layer of the input bump electrode IBMP, an n-channel typeMISFET and a p-channel type MISFET constituting the SRAMs 2 a to 2 c areformed. In the following, a device structure will be described on theassumption that the n-channel type MISFET and the p-channel type MISFETconstituting the SRAMs 2 a to 2 c are formed in the lower layer of theinput bump electrode IBMP. That is, the semiconductor device in thepresent fifth embodiment has an n-channel type MISFET Q1 and a p-channeltype MISFET Q2 and the respective configurations thereof will bedescribed.

In a semiconductor substrate 1S, an element isolation region STI thatseparates elements is formed and in a region (within the semiconductorsubstrate 1S) in which the n-channel type MISFET Q1 is formed amongactive regions divided by the element isolation region STI, a p-typewell PWL is formed and in a region (within the semiconductor substrate1S) in which the p-channel type MISFET Q2 is formed, an n-type well NWLis formed.

The n-channel type MISFET Q1 has a gate insulating film GOX over thep-type well PWL formed within the semiconductor substrate 15, and overthe gate insulating film GOX, a gate electrode G1 is formed. The gateinsulating film GOX is formed from, for example, a silicon oxide filmand the gate electrode G1 is formed from, for example, a laminated filmof a polysilicon film PF and a cobalt silicide film CS, in order toreduce resistance.

However, the gate insulating film GOX is not limited to the siliconoxide film, but can be modified in various ways, and the gate insulatingfilm GOX may be formed from, for example, a silicon oxynitride film(SiON). That is, it may have a structure in which nitrogen is segregatedat the interface between the gate insulating film GOX and thesemiconductor substrate 1S. The silicon oxynitride film has asignificant effect for suppressing the occurrence of interface state inthe film and reducing electron trap compared to the silicon oxide film.As a result, it is possible to improve the hot-carrier resistance of thegate insulating film GOX and the insulation resistance. In addition, itis difficult for impurities to penetrate through the silicon oxynitridefilm, compared to the silicon oxide film. Because of this, by using asilicon oxynitride film as the gate insulating film GOX, it is possibleto suppress the variations in the threshold voltage resulting from thediffusion of impurities in the gate electrode to the side of thesemiconductor substrate 1S. In order to form a silicon oxynitride film,for example, it is only required to perform heat treatment on thesemiconductor substrate 1S in an atmosphere containing nitrogen, such asNO, NO₂, and NH₃. It is also possible to obtain the same effect byperforming heat treatment on the semiconductor substrate 1S in anatmosphere containing nitrogen after forming the gate insulating filmGOX including a silicon oxide film on the surface of the semiconductorsubstrate 1S, and segregating nitrogen to the interface between the gateinsulating film GOX and the semiconductor substrate 1S.

Further, it may also be possible to form the gate insulating film GOXfrom, for example, a high-k dielectric film having the dielectricconstant higher than that of the silicon oxide film. Conventionally,from the standpoint that the insulation resistance is high, theelectrical/physical stability at the interface between silicon andsilicon oxide is excellent, etc., a silicon oxide film is used as thegate insulating film GOX. However, it has been demanded for the gateinsulating film GOX to be extremely thin accompanying theminiaturization of element. If such a thin silicon oxide film is used asthe gate insulating film GOX, a so-called tunneling current is generatedby electrons that flow through the channel of MISFET, tunneling thebarrier wall formed by the silicon oxide film and flowing to the gateelectrode.

Because of this, a material having a dielectric constant higher thanthat of the silicon oxide film is used and a high-k dielectric filmbegins to be used recently, which has the same capacitance but iscapable of increasing the physical film thickness. With a high-kdielectric film, it is possible to increase the physical film thicknesswith the same capacitance, and therefore, the leak current can bereduced. In particular, although the silicon nitride film has adielectric constant higher than that of the silicon oxide film, it isdesirable to use a high-k dielectric film having a dielectric constanthigher than that of the silicon nitride film in the present fifthembodiment.

For example, as a high-k dielectric film having a dielectric constanthigher than that of the silicon nitride film, a hafnium oxide film (HfO₂film) is used, which is one of hafnium oxides, however, instead of thehafnium oxide film, other hafnium-based insulating films, such as aHfAlO film (hafnium aluminate film), a HfON film (hafnium oxynitridefilm), a HfSiO film (hafnium silicate film), and a HfSiON film (hafniumsilicon oxynitride film) can be used. Further, hafnium-based insulatingfilms that have introduced oxides therein, such as tantalum oxide,niobium oxide, titanium oxide, zirconium oxide, lanthanum oxide, andyttrium oxide, can also be used. Because the hafnium-based insulatingfilm has a dielectric constant higher than that of the silicon oxidefilm and the silicon oxynitride film, like the hafnium oxide film, thesame effect when the hafnium oxide film is used can be obtained.

On the side wall on both sides of the gate electrode G1, a sidewall SWis formed and within the semiconductor substrate 1S under the sidewallSW, a shallow n-type impurity diffusion region EX1 is formed as asemiconductor region. The sidewall SW is formed by, for example, aninsulating film, such as a silicon oxide film. Then, outside the shallown-type impurity diffusion region EX1, a deep n-type impurity diffusionregion NR is formed and on the surface of the deep n-type impuritydiffusion region NR, the cobalt silicide film CS is formed.

The sidewall SW is formed so that the source region and the drainregion, which are the semiconductor region of the n-channel type MISFETQ1, have an LDD structure. That is, the source region and the drainregion of the n-channel type MISFET Q1 are formed by the shallow n-typeimpurity diffusion region EX1 and the deep n-type impurity diffusionregion NR. At this time, the impurity concentration of the shallown-type impurity diffusion region EX1 is lower than that of the deepn-type impurity diffusion region NR. Because of this, by forming thesource region and the drain region under the sidewall SW as the shallown-type impurity diffusion region EX1, it is possible to suppresselectric field under the end part of the gate electrode G1 fromconcentrating.

Next, the p-channel type MISFET Q2 has the gate insulating film GOX overthe n-type well NWL formed within the semiconductor substrate 15 andover the gate insulating film GOX, a gate electrode G2 is formed. Thegate insulating film GOX is formed by, for example, a silicon oxidefilm, and the gate electrode G2 is formed by, for example, a laminatedfilm of the polysilicon film PF and the cobalt silicide film CS toreduce resistance. At this time, in the p-channel type MISFET Q2 also,the gate insulating film GOX is not limited to a silicon oxide film butit may also be possible to use a silicon oxynitride film or a high-kdielectric film having a dielectric constant higher than that of asilicon oxide film, like the n-channel type MISFET Q1.

On the side wall on both sides of the gate electrode G2, the sidewall SWis formed and within the semiconductor substrate 1S under the sidewallSW, a shallow p-type impurity diffusion region EX2 is formed as asemiconductor region. The sidewall SW is formed by, for example, aninsulating film, such as a silicon oxide film. Then, outside the shallowp-type impurity diffusion region EX2, a deep p-type impurity diffusionregion PR is formed and on the surface of the deep p-type impuritydiffusion region PR, the cobalt silicide film CS is formed.

The sidewall SW is formed so that the source region and the drainregion, which are the semiconductor region of the p-channel type MISFETQ2, have an LDD structure. That is, the source region and the drainregion of the p-channel type MISFET Q2 are formed by the shallow p-typeimpurity diffusion region EX2 and the deep p-type impurity diffusionregion PR. At this time, the impurity concentration of the shallowp-type impurity diffusion region EX2 is lower than that of the deepp-type impurity diffusion region PR. Because of this, by forming thesource region and the drain region under the sidewall SW as the shallowp-type impurity diffusion region EX2 of low concentration, it ispossible to suppress the electric field under the end part of the gateelectrode G2 from concentrating.

As described above, over the semiconductor substrate 15, the n-channeltype MISFET Q1 and the p-channel type MISFET Q2 are formed. For example,a contact interlayer insulating film CIL including a silicon oxide filmis formed so as to cover the n-channel type MISFET Q1 and the p-channeltype MISFET Q2 and a contact hole is formed so as to penetrate throughthe contact interlayer insulating film CIL. The contact hole is formedso as to reach the source region and the drain region of the n-channeltype MISFET Q1 and the source region and the drain region of thep-channel type MISFET Q2 and a plug PLG1 is formed within the contacthole. The plug PLG1 is formed by filling the contact hole with a barrierconductive film including, for example, a titanium/titanium nitride film(a titanium film and a titanium nitride film formed over the titaniumfilm) and a tungsten film.

Specifically, the contact interlayer insulating film CIL is formed by alaminated film of an ozone TEOS film formed by the thermal CVD methodusing ozone and TEOS as a raw material and a plasma TEOS film formed bythe plasma CVD method using TEOS as a raw material. It may also bepossible to form, for example, an etching stopper film including asilicon nitride film in the lower layer of the ozone TEOS film.

The contact interlayer insulating film CIL is formed by a TEOS filmbecause the TEOS film is a film excellent in the coverage for thebacking step. The backing that forms the contact interlayer insulatingfilm CIL is the semiconductor substrate over which MISFET is formed andwhich has bumps and dips. That is, because MISFET is formed over thesemiconductor substrate 1S, on the surface of the semiconductorsubstrate 1S, a gate electrode is formed, and therefore, the backing hasbumps and dips. Consequently, unless a film is excellent in coverage fora step with bumps and dips, it is not possible to flatten the fine bumpsand dips, resulting in the occurrence of voids etc. Because of this, aTEOS film is used as the contact interlayer insulating film CIL. This isbecause, in a TEOS film that uses TEOS as a raw material, before TEOS,which is a raw material, becomes a silicon oxide film, it forms anintermediate, facilitating movement on the surface of a film beingformed, and therefore, the coverage properties for the backing step areimproved.

The titanium/titanium nitride film constituting a barrier conductivefilm is a film provided to prevent tungsten constituting the tungstenfilm from diffusing into silicon and also to prevent fluorine fromattacking the contact interlayer insulating film CIL and thesemiconductor substrate 1S to inflict damage on them in the CVD methodin which WF₆ (tungsten fluoride) is subjected to reduction processingwhen the tungsten film is formed.

Next, over the contact interlayer insulating film CIL in which the plugPLG1 is formed, a multilayer wiring is formed. The structure of themultilayer wiring will be described below. As shown in FIG. 14, over theplug PLG1 formed in the contact interlayer insulating film CIL, a firstlayer wiring L1 is formed. The first layer wiring L1 is formed by, forexample, a laminated film including a titanium nitride film, an aluminumfilm, and a titanium nitride film. Then, over the contact interlayerinsulating film CIL over which the first layer wiring L1 is formed, aninterlayer insulating film IL1 that covers the first layer wiring L1 isformed. The interlayer insulating film IL1 is formed by, for example, asilicon oxide film. In the interlayer insulating film ILL a plug PLG2that reaches the first layer wiring L1 is formed. This plug PLG2 is alsoformed by embedding a barrier conductive film including atitanium/titanium nitride film and a tungsten film.

Subsequently, over the plug PLG2 formed in the interlayer insulatingfilm ILL a second layer wiring L2 is formed. The second layer wiring L2is formed by, for example, a laminated film including a titanium nitridefilm, an aluminum film, and a titanium nitride film. Then, over theinterlayer insulating film IL1 over which the second layer wiring L2 isformed, an interlayer insulating film IL2 that covers the second layerwiring L2 is formed. The interlayer insulating film IL2 is formed by,for example, a silicon oxide film. In the interlayer insulating filmIL2, a plug PLG3 that reaches the second layer wiring L2 is formed. Thisplug PLG3 is also formed by embedding a barrier conductive filmincluding a titanium/titanium nitride film and a tungsten film.

Next, over the plug PLG3 formed in the interlayer insulating film IL2, athird layer wiring L3 is formed. The third layer wiring L3 is formed by,for example, a laminated film including a titanium nitride film, analuminum film, and a titanium nitride film. Then, over the interlayerinsulating film IL2 over which the third layer wiring L3 is formed, aninterlayer insulating film IL3 that covers the third layer wiring L3 isformed. The interlayer insulating film IL3 is formed by, for example, asilicon oxide film. In the interlayer insulating film IL3, a plug PLG4that reaches the third layer wiring L3 is formed. This plug PLG4 is alsoformed by embedding a barrier conductive film including atitanium/titanium nitride film and a tungsten film.

Subsequently, over the plug PLG4 formed in the interlayer insulatingfilm IL3, a fourth layer wiring L4 is formed. The fourth layer wiring L4is formed by, for example, a laminated film including a titanium nitridefilm, an aluminum film, and a titanium nitride film. Then, over theinterlayer insulating film IL3 over which the fourth layer wiring L4 isformed, an interlayer insulating film IL4 that covers the fourth layerwiring L4 is formed. The interlayer insulating film IL4 is formed by,for example, a silicon oxide film. In the interlayer insulating filmIL4, a plug PLG5 that reaches the fourth layer wiring L4 is formed. Thisplug PLG5 is also formed by embedding a barrier conductive filmincluding a titanium/titanium nitride film and a tungsten film.

The multilayer wiring is formed as described above. In the present fifthembodiment, the multilayer wiring is formed by an aluminum film,however, it may also be possible to form the multilayer wiring by acopper film. That is, the first layer wiring L1 to the fourth layerwiring L4 may be formed by a conductive film containing copper as itsmain component, such as a damascene wiring. That is, after a groove isformed in each of the interlayer insulating film IL1 to the interlayerinsulating film IL4, a conductive film containing copper as its maincomponent is formed inside and outside the groove. Then, it is alsopossible to obtain a structure in which a conductive film is embeddedwithin the groove by polishing the conductive film outside the groove bythe chemical mechanical polishing (CMP) method etc. Specifically, themultilayer wiring may be formed from copper (Cu) or copper alloy (alloyof copper (Cu) and aluminum (Al), magnesium (Mg), titanium (Ti),manganese (Mn), iron (Fe), zinc (Zn), zirconium (Zr), niobium (Nb),molybdenum (Mo), ruthenium (Ru), palladium (Pd), silver (Ag), gold (Au),indium (In), lanthanoid-based metal, actinoid-based metal, etc.).

Further, the interlayer insulating films IL1 to IL4 may be formed by alow dielectric constant film having a dielectric constant lower thanthat of a SiOF film. Specifically, the interlayer insulating films IL1to IL4 may be formed by either of a SiOC film having vacancies, a MSQfilm having vacancies (methylsilsesquioxane, a silicon oxide film formedby an application step and having a Si—C bond, or a silsesquioxanecontaining carbon), a HSQ film having vacancies (hydrogensilsesquioxane, a silicon oxide film formed by an application step andhaving a Si—H bond, or silsesquioxane containing hydrogen). The size(diameter) of a vacancy is, for example, about 1 nm.

Next, over the plug PLG5 formed in the interlayer insulating film IL4,the uppermost layer wirings TM1, TM2, TM3 are formed. The uppermostlayer wirings TM1, TM2, TM3 are formed by, for example, a laminated filmincluding a titanium nitride film, an aluminum film, and a titaniumnitride film. Then, over the interlayer insulating film IL4 over whichthe uppermost layer wirings TM1, TM2, TM3 are formed, an interlayerinsulating film (surface protection film) IL5 is formed so as to coverthe uppermost layer wirings TM1, TM2, TM3. The interlayer insulatingfilm IL5 is formed by, for example, a laminated film including a siliconoxide film and a silicon nitride film formed over the silicon oxidefilm.

Further, in the interlayer insulating film IL5, the opening CNT1 thatreaches the uppermost layer wiring TM1 is formed and a conductivematerial is filled in the opening CNT1. The input bump electrode IBMP1is formed over the interlayer insulating film IL5 in which the openingCNT1 is formed. The input bump electrode IBMP1 is formed by an underbump metal (UBM) film, which is a backing film, and a gold film formedover the UBM film. The UBM film may be formed by using, for example, thesputtering method and formed by, for example, a single layer film, suchas a titanium film, a nickel film, a palladium film, a titanium/tungstenalloy film, a titanium nitride film, and a gold film, or a laminatedfilm thereof. Here, the UBM film is a film having a barrier function tosuppress or prevent metal elements of the gold film from moving to theside of the multilayer wiring or conversely, the metal elements of themultilayer wiring from moving to the side of the gold film, in additionto a function to improve adhesion between the input bump electrode IBMP1and the surface protection film (interlayer insulating film IL5).

The semiconductor device in the present fifth embodiment is formed asdescribed above. At this time, the three uppermost layer wirings TM1,TM2, TM3 are formed in the lower layer that overlaps the input bumpelectrode IBMP1 in a planar view as a result.

Subsequently, for example, a structure in which two openings are coupledto one input bump electrode IBMP will be described. FIG. 15 is a diagramshowing one input bump electrode IBMP1. In FIG. 15, the direction inwhich the long side LS1 of the semiconductor chip CHP2 extends isreferred to as the X direction and the short-side direction of thesemiconductor chip CHP2 is referred to as the Y direction. As shown inFIG. 15, the input bump electrode IBMP1 is in the form of a rectangleand in the lower layer of the input bump electrode IBMP1, the threeuppermost layer wirings TM1 to TM3 are arranged. The input bumpelectrode IBMP1 is electrically coupled to the uppermost layer wiringTM1 via a conductive material filled in an opening CNT1 a andelectrically coupled also to the uppermost layer wiring TM3 via aconductive material filled in an opening CNT1 b. A device structureformed in the lower layer of the input bump electrode IBMP1 thusconfigured will be described with reference to FIG. 16.

FIG. 16 is a section view cut by A-A line in FIG. 15, a section viewshowing a configuration of the semiconductor device in the present fifthembodiment. The device structure shown in FIG. 16 is substantially thesame as that shown in FIG. 14, and therefore, a different structure willbe described. The device structure shown in FIG. 16 differs from thatshown in FIG. 14 in the coupling relationship between the input bumpelectrode IBMP1 and the uppermost layer wirings TM1, TM2, TM3. The inputbump electrode IBMP1 shown in FIG. 16 is coupled to the two openings,CNT1 a and CNT1 b. Then, via the opening CNT1 a, the input bumpelectrode IBMP1 and the uppermost layer wiring TM1 are electricallycoupled and via the opening CNT1 b, the input bump electrode IBMP1 andthe uppermost layer wiring TM3 are electrically coupled. The other partsof the device structure are the same as those of the device structureshown in FIG. 14. In the manner described above, the device structure isformed, in which the two openings CNT1 a, CNT1 b are coupled to oneinput bump electrode IBMP.

Sixth Embodiment

In a sixth embodiment, a step of mounting the semiconductor chip CHP2constituting an LCD driver over a mounting substrate (glass substrate)will be described. First, by using the normal semiconductormanufacturing technique, a semiconductor element, such as MISFET, isformed over the semiconductor substrate and then, a multilayer wiring isformed over the semiconductor substrate over which the semiconductorelement is formed. Then, after forming an uppermost layer wiring formedin the uppermost layer of the multilayer wiring, a surface protectionfilm that covers the uppermost layer wiring is formed. Then, an openingthat reaches the uppermost layer wiring is formed in the surfaceprotection film and the opening is filled and at the same time, a bumpelectrode (input bump electrode and output bump electrode) is formedover the surface protection film. Then, by dicing the semiconductorsubstrate, it is possible to obtain the individual semiconductor chipsCHP2 as shown in FIG. 4.

Next, a step of mounting the semiconductor chip CHP2 formed as describedabove over a mounting substrate (glass substrate) by adhesion will bedescribed. FIG. 17 shows a case where the semiconductor chip CHP2 ismounted over a glass substrate 10 (COG: Chip On Glass). As shown in FIG.17, over the glass substrate 10, a glass substrate 11 is mounted andthus a display part of an LCD is formed. Then, over the glass substrate10 in the vicinity of the display part of the LCD, a region is formedwhere the semiconductor chip CHP2, which is an LCD driver, is mounted.In the semiconductor chip CHP2, the input bump electrode IBMP and theoutput bump electrode OBMP are formed and the input bump electrode IBMPand the output bump electrode OBMP are coupled to electrodes 10 a (ITOelectrode) formed over the glass substrate 10 via an anisotropicconductive film ACF. The anisotropic conductive film ACF is configuredso as to have an insulating layer 12 and metal particles 13.

In this step, the semiconductor chip CHP2 and the electrodes 10 a formedover the glass substrate 10 are aligned using a camera C. By thisalignment, the accurate position of the semiconductor chip CHP2 isgrasped by the camera C recognizing an alignment mark formed in thesemiconductor chip CHP2.

FIG. 18 is a section view showing the state where the semiconductor chipCHP2 is mounted over the anisotropic conductive film ACF after thealignment by the camera C is performed. At this time, the accuratealignment is performed between the semiconductor chip CHP2 and the glasssubstrate 10, and therefore, over the electrode 10 a, the input bumpelectrode IBMP and the output bump electrode OBMP are located.

Subsequently, as shown in FIG. 19, the input bump electrode IBMP and theoutput bump electrode OBMP are coupled to the electrode 10 a via theanisotropic conductive film ACF. The anisotropic conductive film ACF isa film obtained by molding a mixture of thermosetting resin and finemetal particles having conductivity into the form of a film. The metalparticle is a sphere in which a nickel layer and a gold-plated layer areformed mainly from the inside and an insulating layer is overlapped onthe outermost side, having a diameter of 3 to 5 μm. In this state, whenthe semiconductor chip CHP2 is mounted over the glass substrate 10, theanisotropic conductive film ACF is sandwiched between the electrode 10 aof the glass substrate 10, and the input bump electrode IBMP and theoutput bump electrode OBMP of the semiconductor chip CHP2. Then, if thesemiconductor chip CHP2 is pressurized while heating with a heater etc.,a pressure is applied only to the portion corresponding to the inputbump electrode IBMP and the output bump electrode OBMP. Because of this,the metal particles dispersed within the anisotropic conductive film ACFcome into contact with and overlap one another, and are pressed againstone another. As a result, an electrically conductive path is formed inthe anisotropic conductive film ACF via the metal particles. Metalparticles in a portion of the anisotropic conductive film ACF to whichno pressure is applied still hold the insulating layer formed on thesurface of the metal particle, and therefore, the insulation betweeninput bump electrodes IBMP located side by side and between the outputbump electrodes OBMP located side by side is held. Because of this,there is an advantage that the semiconductor chip CHP2 can be mountedover the glass substrate 10 without causing short circuit even if theseparation between the input bump electrodes IBMP or the separationbetween the output bump electrodes OBMP is narrow.

Subsequently, as shown in FIG. 20, the glass substrate 10 and a flexibleprinted circuit FPC is also coupled via the anisotropic conductive filmACF. As described above, in the semiconductor chip CHP2 mounted over theglass substrate 10, the output bump electrode OBMP is electricallycoupled to the display part of the LCD and the input bump electrode IBMPis coupled to the flexible printed circuit FPC.

FIG. 21 is a diagram showing an overall configuration of an LCD (liquidcrystal display device) 15. As shown in FIG. 21, a display part 14 ofthe LCD is formed over a glass substrate and an image is displayed onthe display part 14. Over the glass substrate in the vicinity of thedisplay part 14, the semiconductor chip CHP2, which is an LCD driver, ismounted. In the vicinity of the semiconductor chip CHP2, the flexibleprinted circuit FPC is mounted and between the flexible printed circuitFPC and the display part 14 of the LCD, the semiconductor chip CHP2,which is a driver, is mounted. In this manner, it is possible to mountthe semiconductor chip CHP2 over the glass substrate. As describedabove, it is possible to mount the semiconductor chip CHP2, which is anLCD driver, in the liquid crystal display 15.

Seventh Embodiment

In a seventh embodiment, a plane layout of output bump electrodes,uppermost layer wirings, and an output protection circuit will bedescribed. FIG. 22 is an enlarged view of a region in the vicinity ofthe long side LS2 of the semiconductor chip CHP2 constituting the LCDdriver shown in FIG. 4.

As shown in FIG. 22, output bump electrodes OBMP1 close to the internalcircuit of the semiconductor chip CHP2 and output bump electrodes OBMP2close to the side of the long side LS2 are arranged in a staggeredmanner. A plurality of the output bump electrodes OBMP1 and a pluralityof the output bump electrodes OBMP2 are arranged in the direction (Xdirection) along the long side LS2, respectively. Over a semiconductorsubstrate under the output bump electrode OBMP1 and the output bumpelectrode OBMP2, the output protection circuit 4 is arranged. In theregion of the output protection circuit 4, a plurality of semiconductorelements for circuit protection as shown in FIG. 2 or FIG. 3 is formedand electrically coupled to the output bump electrode OBMP1 and theoutput bump electrode OBMP2, respectively. The output protection circuit4 is electrically coupled to the output bump electrode OBMP1 and theoutput bump electrode OBMP2 via an uppermost layer wiring TM5 or anuppermost layer wiring TM6. Further, the uppermost layer wiring TM5 andthe uppermost layer wiring TM6 are coupled to the output bump electrodeOBMP1 and the output bump electrode OBMP2, respectively, via an openingCNT6 or an opening CNT7, respectively.

Here, the opening CNT7 of the output bump electrode OBMP2 is provided ata position close to the internal circuit rather than to the side of thelong side LS2. Due to this, an uppermost layer wiring TM7 (power supplywiring) (reference potential Vss) and an uppermost layer wiring TM8(power supply wiring) (external power supply potential Vcc) can berouted around the outer circumference of the semiconductor chip CHP2.That is, it is possible to effectively use the region at the top part ofthe output protection circuit 4 and at the lower part of the output bumpelectrode OBMP2. As described above, in the semiconductor chip CHP2 inthe present seventh embodiment, the output bump electrode OBMP1 and theoutput bump electrode OBMP2 are also devised to reduce the chip size.

That is, the characteristic in the present seventh embodiment is thatthe output bump electrodes OBMP2 arranged at the position close to thelong side LS2 and the output bump electrodes OBMP1 arranged at theposition farther from the long side LS2 than the output bump electrodesOBMP2 are provided as the output bump electrodes arranged in a staggeredmanner. Then, under the output bump electrode OBMP1, the uppermost layerwiring TM5 is formed and under the output bump electrode OBMP2, theuppermost layer wiring TM6 is formed. At this time, the output bumpelectrode OBMP1 is coupled to the uppermost layer wiring TM5 via theopening CNT6 formed in the insulating film and the output bump electrodeOBMP2 is coupled to the uppermost layer wiring TM6 via the opening CNT7formed in the insulating film. It is characteristic that the position atwhich the opening CNT6 is formed is a position closer to the long sideLS2 than the center of the output bump electrode OBMP1 and the positionat which the opening CNT7 is formed is a position farther from the longside LS2 than the center of the output bump electrode OBMP2.

Unlike the input bump electrodes IBMP shown in the third embodimentdescribed above, all of the positions of the openings CNT7 of the outputbump electrodes OBMP2 are the same and all of the positions of theopenings CNT6 of the output bump electrodes OBMP1 are the same. That is,the input bump electrodes IBMP are formed linearly and the positions ofsome openings (for example, the openings CNT1 to CNT3 in FIG. 8 and FIG.9) are different. However, the output bump electrodes OBMP1 are formedlinearly and the positions of the openings CNT6 are the same. The outputbump electrode OBMP2 are formed in the form of a straight line differentfrom that of the output bump electrodes OBMP1 and the positions of theopenings CNT7 are the same.

With the technique disclosed in the present seventh embodiment asdescribed above, it is possible to reduce the size in the short-sidedirection of the semiconductor chip CHP2.

The technique disclosed in the present seventh embodiment can also beapplied to the other embodiments described above.

Eighth Embodiment

In an eighth embodiment, a case is illustrated, where a dummy regionwhere no semiconductor element is formed is arranged in a region thatoverlaps the input bump electrodes IBMP1, IBMP2 in a planar view. FIG.23 is a section view cut along A-A line in FIG. 13, a section viewillustrating the present eighth embodiment.

For example, in the fifth embodiment described above, the example isshown, where the internal circuit IU is arranged in the region thatoverlaps the input bump electrodes IBMP1, IBMP2 in a planar view,however, this is not limited, the region that overlaps the input bumpelectrodes IBMP1, IBMP2 in a planar view may be a dummy region where nosemiconductor element is formed. The dummy region is a region of asemiconductor substrate defined by the element isolation region STI,which does not contribute to the circuit operation of the semiconductordevice.

In FIG. 23, as an example of a dummy region, a dummy pattern DP providedto prevent dishing is shown. In the dummy pattern DP, a plurality ofpatterns is provided in the same form and formed at the same pitch, andarranged regularly.

As described above, in the present eighth embodiment also, as in thefifth embodiment described above, it is possible to cause a plurality ofwiring layers to pass through the lower layer of the input bumpelectrodes IBMP1, IBMP2, and therefore, it is possible to increase thedegree of freedom in wiring layout.

Further, the dummy pattern DP is provided in a region that overlaps theinput bump electrodes IBMP1, IBMP2 in a planar view, and therefore, theflatness of each wiring layer can be improved.

The technique disclosed in the present eighth embodiment can also beapplied to the other embodiments described above.

The invention made by the inventors of the present invention isdescribed based on the embodiments as described above, however, thepresent invention is not limited to the embodiments and it is obviousthat there can also be various modifications within the scope notdeparting from its gist.

In the present embodiments, the drive device (LDC driver) for liquidcrystal display is illustrated, however, this is not limited and thepresent invention can also be applied to other drive devices fordisplay, such as an organic EL. Further, the present invention is notlimited to a drive device but can be applied to other semiconductordevices. In particular, it is preferable to apply the present inventionto a case where a semiconductor chip is in the form of a rectangle.

The present invention can be used widely in the manufacturing industrythat manufactures semiconductor devices.

What is claimed is:
 1. A semiconductor device comprising: (a) asemiconductor substrate of substantially rectangular shape having a pairof long edges and a pair of short edges; (b) an internal circuitincluding a plurality of MISFETs formed over the semiconductorsubstrate; (c) a plurality of protection elements formed over thesemiconductor substrate so as to protect the internal circuit againststatic electricity; (d) a first insulating film formed over thesemiconductor substrate so as to cover the plurality of MISFETs and theplurality of protection elements; and (e) a plurality of bump electrodesformed over the first insulating film, the plurality of bump electrodesbeing arranged along a first long edge of the pair of long edges,wherein the plurality of bump electrodes are bump electrodes forreceiving input signals from an external device, wherein the pluralityof protection elements are electrically coupled between the respectiveplurality of bump electrodes and the internal circuit, wherein theplurality of bump electrodes include a first bump electrode and a secondbump electrode, wherein the plurality of protection elements include afirst protection element and a second protection element, wherein thefirst protection element electrically coupled to the first bumpelectrode is disposed at a position overlapped with the first bumpelectrode in a planar view when viewed from a direction perpendicular tothe substrate, and wherein the second protection element electricallycoupled to the second bump electrode is disposed at a position differentfrom a position overlapped with the second bump electrode in a planarview when viewed from a direction perpendicular to the substrate.
 2. Thesemiconductor device according to claim 1, wherein the third bumpelectrode is disposed so as to overlap parts of the plurality of MISFETsin a planar view when viewed from a direction perpendicular to thesubstrate.
 3. The semiconductor device according to claim 1, wherein thesecond protection element is disposed at an inner side of thesemiconductor substrate than the plurality of bump electrodes in a firstdirection along the pair of short edges of the semiconductor substratein a planar view.
 4. The semiconductor device according to claim 1,further comprising: (f) another plurality of protection elements formedover the semiconductor substrate so as to protect the internal circuitagainst static electricity; (g) another plurality of bump electrodesformed over the first insulating film, the other plurality of bumpelectrodes being arranged along a second long edge of the pair of longedges, wherein the other plurality of bump electrodes are bumpelectrodes for sending output signals to another external device, andwherein the other plurality of protection elements are electricallycoupled between the other respective plurality of bump electrodes andthe internal circuit.
 5. The semiconductor device according to claim 4,wherein the other plurality of protection elements are disposed at aposition overlapped with the other plurality of bump electrodes in aplanar view when viewed from a direction perpendicular to the substrate.6. The semiconductor device according to claim 1, wherein the pluralityof bump electrodes are arranged linearly while the other plurality ofbump electrodes are arranged in a staggered manner.
 7. The semiconductordevice according to claim 1, wherein the respective plurality ofprotection elements includes two diodes.
 8. The semiconductor deviceaccording to claim 1, wherein the respective plurality of protectionelements includes two transistors.
 9. The semiconductor device accordingto claim 1, wherein the semiconductor device is an LCD driver configuredto drive a liquid crystal display device.